vendor branches need .gitignore
Updated puzzles to r9830
Merge branch 'sgt-puzzles' r9830. Rename my emcc port to "html5".

SGT & I overlapped doing html5 ports, and both chose "emcc" as the Makefile extension. His is different enough from mine that it's easier to just rename mine and maintain it alongside his, at least for now.
Keys: Don't steal Mac browser Cmd+Arrow navigation shortcuts