Propose: Use YAML for generated files

[DFelipehDEV]

I want to propose to use YAML instead of format in .yyd and room.txt to make it more consistent and easier to parse by external tools.
This would also benefit the YAML extension for GM
This:

+Solids
	+Main
		|sprSolidMask01
		|sprSolidMask02
	+Platform
		|sprPlatformMask01
		|sprPlatformMask01Spin

could easily be replaced by this:

Solids:
  Main:
    - sprSolidMask01
    - sprSolidMask02
  Platform:
    - sprPlatformMask01
    - sprPlatformMask01Spin