Converted composite chart vows tests to jasmine specs, and fixed cleanup
Added support for right y-axes using #useRightYAxis()

This applies to coordinate grid charts and composite charts. Also added
an example similar to the jsfiddle renderlet example on the mailing
list.
Converted line chart vows tests to jasmine specs
Hopefully fixed flakey lineChart specs by accounting for timezone
Fixed merge conflict with #402
Second attempt to fix flakey lineChart specs
De-linted jasmine specs
Merge pull request #415