Added Unit Tests for Lpar class.
Added Unit Tests for Lpar class.

Details:
- Added Unit Tests for Lpar operations.
- Fixed issue #8

Signed-off-by: Juergen Leopold <2ef4e6fc356c4a0c570adb4e83b64b658f380892@de.ibm.com>

zhmcclient/python-zhmcclient,zhmcclient/python-zhmcclient