add language declaration and samples for LoomScript

LoomScript is the scripting language for the Loom SDK.
It has an ActionScript3-like syntax with added C#-esque capabilities.

Loom SDK: https://github.com/LoomSDK/LoomSDK

Some GitHub projects using LoomScript:

* https://github.com/bengarney/ScoreKeeper
* https://github.com/Crwth/MultiMovieClip
* https://github.com/dbltnk/ouya-loom-jam
* https://github.com/elevatefun/DragonBonesLoomScript
* https://github.com/esDotDev/RunnerMark-Loom
* https://github.com/ghroot/AshLoom
* https://github.com/johnbatty/WhackAPotato
* https://github.com/lunarraid/LoomIsoProject
* https://github.com/pixeldroid/spec-ls
* https://github.com/ravensinth/LoomSnake
* https://github.com/RivelloMultimediaConsulting/LoomDemos
* https://github.com/southpawfishel/Gestouch-Loom2D
* https://github.com/southpawfishel/LoomTMX
@arfon I think this is ok too. I had some concerns before but since we are sure that every LoomScript code will contain a package declaration, if it doesn't, it must be a LiveScript program. Of course, we'll have to change this if a third language is defined with the `.ls` extension.