Some array polyfills

Array.prototype.find
Array.prototype.findIndex
Array.prototype.fill
Fix some issues with find and toInteger

- find should skip holes
- toInteger should call toNumber
0.0.42
Commit the generated code to gh-pages.
Rebase.
Recompile
Recompile
Update built files after merge
Rebuild traceur-runtime
Update runtime and commit binary
Rebuild
Recompile
Merge and rebuild
Rebase; commit binaries for 0.0.39
Rebase; commit binaries for 0.0.40
Rebase; commit binaries for 0.0.41
Rebase; commit binaries for 0.0.42