Issue #309 Implemented MkGists.remove()
Issue #331 - Implemented unstar method
Merge pull request #339 from carlosmiranda/309

#339: pull request Issue #309 Implemented MkGists.remove()
Merge pull request #341 from lthuangiang/331

#341: pull request Issue #331 - Implemented unstar method
Merge pull request #35 from jcabi/master

merge from master to my branch