Fixes the following GCC 5 warnings:
```
core/os/file_access.cpp:49:19: warning: the address of 'FileAccess::create_func' will always evaluate as 'true' [-Waddress]
servers/audio_server.cpp:192:70: warning: comparison with string literal results in unspecified behaviour [-Waddress]
drivers/gles2/rasterizer_storage_gles2.cpp:4095:90: warning: NULL used in arithmetic [-Wpointer-arith]
modules/gdnative/register_types.cpp:237:3: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]
platform/android/export/export.cpp:207:1: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]
modules/gdscript/gdscript.h:150:67: warning: returning reference to temporary [-Wreturn-local-addr]
servers/physics_2d/collision_object_2d_sw.h:119:56: warning: returning reference to temporary [-Wreturn-local-addr]
servers/physics_2d/collision_object_2d_sw.h:123:56: warning: returning reference to temporary [-Wreturn-local-addr]
servers/physics_2d/collision_object_2d_sw.h:127:50: warning: returning reference to temporary [-Wreturn-local-addr]
servers/physics_2d/collision_object_2d_sw.h:131:52: warning: returning reference to temporary [-Wreturn-local-addr]
editor/plugins/skeleton_editor_plugin.cpp:34:36: warning: extra tokens at end of #include directive
modules/bullet/bullet_types_converter.cpp:31:9: warning: #pragma once in main file
editor/import/editor_scene_importer_gltf.cpp:1996:51: warning: name lookup of 'i' changed
modules/visual_script/visual_script_property_selector.cpp:402:45: warning: name lookup of 'E' changed
scene/gui/tree.cpp:1268:25: warning: name lookup of 'i' changed
scene/resources/visual_shader.cpp:808:32: warning: name lookup of 'i' changed
```
Fixes the following GCC 5 warnings:
```
core/io/resource_format_binary.cpp:1721:29: warning: suggest parentheses around arithmetic in operand of '|' [-Wparentheses]
core/typedefs.h:108:24: warning: suggest parentheses around comparison in operand of '!=' [-Wparentheses]
editor/plugins/spatial_editor_plugin.cpp:2202:58: warning: suggest parentheses around comparison in operand of '!=' [-Wparentheses]
editor/plugins/spatial_editor_plugin.cpp:5002:12: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
main/input_default.cpp:346:59: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
main/input_default.cpp:348:60: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
main/input_default.cpp:579:57: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
modules/gridmap/grid_map_editor_plugin.cpp:613:14: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses]
modules/theora/video_stream_theora.cpp:335:34: warning: suggest parentheses around '+' in operand of '&' [-Wparentheses]
modules/theora/video_stream_theora.cpp:336:35: warning: suggest parentheses around '+' in operand of '&' [-Wparentheses]
modules/visual_script/visual_script_property_selector.cpp:215:38: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
scene/gui/rich_text_label.cpp:424:84: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
scene/gui/rich_text_label.cpp:512:80: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
scene/gui/scroll_container.cpp:173:36: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
scene/gui/scroll_container.cpp:173:86: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
scene/gui/tree.cpp:1419:98: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
```
We're not formally using C++11 yet so those trigger compilation warnings
(at least with GCC 5):
./main/input_default.h:122:30: warning: non-static data member initializers only available with -std=c++11 or -std=gnu++11
CursorShape default_shape = CURSOR_ARROW;
^
Note: We may allow those eventually (especially for non-int static const),
but most of current occurrences were inconsistent with all other classes.
See also http://www.stroustrup.com/C++11FAQ.html#member-init
This allows more consistency in the manner we include core headers,
where previously there would be a mix of absolute, relative and
include path-dependent includes.
* Prototype faster function call ux.
* Work on general search ux.
* Able to create nodes from search.
* Show class for variables but not methods.
* Get actions search working.
* Descriptions now show for both methods and properties.
* Enable zooming on mouse wheel up and down.
* Make the drag trigger on right mouse button.
* Search now shows for action visual script nodes.
* Able to search visual node names.
* Search works better.
* Change zooming scale to hide artifacts better.
* Remove zoom changes
* Select from base should check properties too like the other functions.
* Seq_connect flag is needed to set sequence lines correctly.
* Remove comment
* Code cleanup with function names and arguments.
* Use brief description for search descriptions.
* Clean and fix bug with input nodes connecting with sequence lines.
* Add a warning and fix some edge conditions with sequence into data lines and vice versa.
* Don't search functions when pulling from a sequence node.
* Don't show actions when pulling from a data line.
* Set set and get properties.
* Convert visual script operators to the correct type
* Create a function preset finds only functions.
* Singletons can now find functions.
* Add shift-a for generic search.
* Add brief descriptions for Visual Script nodes.
* Search boxes can now filter names.
* Add bigger hit zones to node connect.
* For the drop zones, make all the rect2 areas the same size.
* Function names in visual script node should be lower case so that search works better.
* Use the convention of capitalize() for set, set, visual script nodes and methods.
* Make search more general. Ignore "_" and make case-insensitive. Also made the search window smaller and remove extra info from search
* Make type_cast use the connecting node's type and remove use of found variable.
* Fix case where you call an instance's call function where it becomes an invalid call.
* Make get_visual_node_names use a set of filters, move action creations and fix bug with sequence node connections.
* Make the window bigger.
* Make connect_data and connect_seq more robust.
* Add icons to search items.
* Add vs constructors in shift-a menu.
* Operators, builtins and constructors show type name. Fix several problems with port connections.
* In shift-a mode search everything.
* Code cleanup
* Work on autocompleting the type.
* Use type guess in action creation.
* Check if type hint string exists in object variables when generating the visual script search.
* Add the hint to SceneTree.
* Add original type detection.
* Make type casting great again. This puts the type casted base type as the data output type string hint.
* Pass the type in a VisualScriptFunctionCall too.
* Set the base type correctly in VisualScriptFunctionGet and VisualScriptFunctionSet using hint string.
* Make sure the instance is passed in VisualScriptPropertySet.
* Restore search on the node's type.
* Remove dependencies from graph_edit.
* Remove dependencies from property_selector and name the class visual_script_property_selector.
* Extract hot zones into a function.
* Move hot_zones constants into default theme.
* Bigger capture zones.
* Clean messy port_grab_distance variables.
* Remove RMB functionality.
* Remove memory leak on showing visual script descriptions.
* Read the port_grab_distance constants on enter tree and theme changed.
