Add job-show to CLI

Change-Id: Ibfb47ca21b810ccab5bab6562a41c4f88c8e0c7a
Implements: blueprint python-savannaclient-cli
Add job-delete to CLI

Change-Id: I6b61e814db648cbbd487b56978f9e45ed522719f
Implements: blueprint python-savannaclient-cli