Add new tests for MockApp, fix skipped tests

This is last commit that fully implement blueprint
that is mentioned below:
- there were a few skipped tests (domain name validation, creation env from app catalog page), now they are fixed
- new tests for MockApp were added: tests for of different type field validation, creation of MockApp field and so on.

Implements blueprint: refactor-ui-tests

Change-Id: I646b9886acbd6a9deba2cced91c5398865b2ac61
Merge "Add new tests for MockApp, fix skipped tests"