* Map is unnecessary and inefficient in almost every case.
* Replaced by the new HashMap.
* Renamed Map to RBMap and Set to RBSet for cases that still make sense
(order matters) but use is discouraged.
There were very few cases where replacing by HashMap was undesired because
keeping the key order was intended.
I tried to keep those (as RBMap) as much as possible, but might have missed
some. Review appreciated!
* Its not and will not be used for streaming.
* Streaming will be implemented in 4.1 and it will work different.
* It makes more sense to be called CompressedTexture since it imports and compresses texture files.
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.
