Merge pull request #46 from jcabi/master

merge from master to my repo
Issue #326 Implemented fetching of readme file from default branch.
MkReleases remove method implemented.
MkReleases remove method implemented. Style fix.
removed puzzle definition
Issue #430 RepoCommit interface was added
Issue #360 Added tests for MkPull json and patch operations.
Merge pull request #47 from jcabi/master

merge from master to my repo
Issue #470 - MkPullComments should be able to fetch a single pull comment
Merge pull request #482 from lthuangiang/470

#482: pull request Issue #470 - MkPullComments should be able to fetch a single pull com…
Merge pull request #477 from longtimeago/430

#477: pull request Issue #430 RepoCommit interface was added
Merge pull request #474 from andrescandal/377

#474: pull request Issue #377 Implemented.
Merge pull request #48 from jcabi/master

merge from master to my repo
Issue #445 - Mock for pull comment
Issue #360 Addressed review comments.
Merge pull request #484 from lthuangiang/445

#484: pull request Issue #445 - Mock for pull comment
Merge pull request #481 from carlosmiranda/360

Issue #360 Added tests for MkPull json and patch operations
Merge pull request #463 from carlosmiranda/326

#463: pull request Issue #326 Implemented fetching of readme file from default branch.
Merge branch 'master' of https://github.com/jcabi/jcabi-github into 258