Issue #221: Added tests for MkSearch.repos(), MkSearch.issues(), and MkSearch.users()
Issue #221: Implemented methods MkSearch.repos(), MkSearch.issues(), and MkSearch.users()
Merge branch 'master' into issue221

Conflicts:
	src/test/java/com/jcabi/github/mock/MkSearchTest.java
Issue #221: Fixed a problem in a test
Merge pull request #257 from asinyagin/issue221

Issue #221