Properly skip SFTPLargeFileTest when environment variables not defined.
Update Code Sniffer to version 1.5.6
Merge pull request #563 from bantu/code-sniffer-1.5.6

Update Code Sniffer to version 1.5.6

* bantu/code-sniffer-1.5.6:
  Update Code Sniffer to version 1.5.6
Merge pull request #562 from bantu/properly-skip-SFTPLargeFileTest

Properly skip SFTPLargeFileTest when environment variables not defined.

* bantu/properly-skip-SFTPLargeFileTest:
  Properly skip SFTPLargeFileTest when environment variables not defined.