Unit test for class GerritQueryHandler

Change-Id: I65e503f130a524083bd05edbcfac8a808860510b
Added support for query full commit message.

Added params if --commit-message should be appended to the command call.
The change is compatible with all old behavior, what unit test show.

Change-Id: I02653ee3b1c1eaeec283f279501d7400e967adfe
Merge pull request #92 from slawekjaranowski/master

Support for query full commit message from gerrit and unit test for GerritQueryHandler