Took the opportunity to undo the Godot changed made to the
opus source. The opus module should eventually be built in its
own environment to avoid polluting others with too many include
dirs and defines.
TODO: Fix the platform/ stuff for opus.
(cherry picked from commit d9a291f641)
speex module was only added while cherry-picking, as speex is removed
in the master branch but we don't want to break compatibility in 2.1.x.
Unbundling wasn't done as the module uses the internal speex_free,
so it would require some more work.
-fixed TouchScreenButton with stretch2d
-fixed(?) OSX crash on startup (test!!)
-compilation fixes on windows
-CollisionPolygon editor works again
-find buttons en find dialog
-TileMap editor cleanup (removed "error", made nicer)
-viewport flicker fixed
-make .scn default extension for saving scenes
-export the rest of the network classes to gdscript
