Update .gitignore to ignore files in ElmFiles/ directories
Update .gitignore to ignore files in ElmFiles/ directories

Also clean out some old stuff that no longer exists in the compiler.

pairyo/elm-compiler,Axure/elm-compiler,JoeyEremondi/elm-pattern-effects,5outh/Elm,laszlopandy/elm-compiler,deadfoxygrandpa/Elm,mgold/Elm