1) Fixed paths issues for Linux system by adding file separator wrapper (both on client and server sides).
2) Removed redundant imports.
3) Added NPE checks for Command container.
4) Added new images / script for Linux tests.
5) Added Linux tests to cover existing functionality.
1) Revised tests structure: moved windows tests into single class.
2) Refreshed win images.
3) Minor fields renaming.
4) README revising.
Merge pull request #78 from sskuts/master

RemoteServer / RESTClient updates