Issue #21: Gist forking
RtRepoTest fetchKeys test method added.
Repo and RtRepo enhanced with keys method
DeployKey added to API
remove unused import from RtDeployKeysTest
MkDeployKeys implemented with Test Case
Merge pull request #139 from asinyagin/21

#139: pull request Issue #21: Gist forking
Code Style fixes for DeployKeys feature
Merge branch '119'