Initial commit of WebIDL grammar.
Added W3C copyright hint.
Updated contributors agreement.
Since each grammar might have its own license, the contributions.txt makes no sense; i'm removing
Removed copyright hint of WebIDL as discussed with WebIDL author.
Update to newest draft version.
merge webidl grammar from rainerschuster
allow line comment on last line
Added check for newline or EOF to LINE_COMMENT
Merge pull request #5 from cowang/terrys_change

Terrys change
Merge pull request #2 from antlr/master

Include change to Terry's Java.g4