Removes some unnecessary includes from `editor_node.h`, and instead add
those where they're used.
Removes unnecessary `editor_node.h` includes in various editor classes.
Renames `dynamicfont` to `dynamic_font` in a couple files.
Misc cleanup while jumping through that rabbit hole.
Renamed to ActionMapEditor as it is more generic and can be used for more than just the InputMapEditor if required.
This also includes a new Event Configuration dialog (previously "Press A key...") which can be used to create and edit InputEvents for any use - like the Project Settings input map, or the Editor Settings shortcuts.
