Fix joint behaviour of Back button and 3-steps Create Service Wizard.

1. Return Back button to the template for 2nd Wizard's step.
2. Restore field values on 2nd step on return from 3rd step.

Fixes: bug MRN-24
Change-Id: I253a15e2f791b14c972cef838f9ffb6697b413c3
Merge "Fix joint behaviour of Back button and 3-steps Create Service Wizard."