Add copy command support.
Extended UNLOAD and COPY commands
some fixes, update version number to 0.5
Set version number to 0.5.0a to mark it as beta
Fix tests for CopyCommand / UnloadCommand
Merge remote-tracking branch 'robertengel/master' into develop
version bump to 0.4.1-run2
Merge branch 'release/0.4.1-run2' into master_run