Upgrade django-pyscss to version 1.0.2

Change-Id: Ie57de8314df08f3353e65ba6a46f186d1d28af90
Closes-bug: #1349774
Fix Volume DeleteBackup success message

Change-Id: Iba33aa974c3074c7b8190a93dc14ebf35c3a8c5d
Closes-Bug: #1352583
Fix unexpected return from Step::__init__()

The __init__() method should always returns None, this patch fix a unexpected
return statement with a TypeError exception, which should be corrected to a
raise statement.

Change-Id: I96d081ab23ac499d6151161d1ae59864c78ea44e
Closes-Bug: 1353270
Merge "Upgrade django-pyscss to version 1.0.2"
Add test skip decorator when service not available

Adding services_required decorator that can be used for decorating test classes
as well as test methods. Decorator expects as arguments services that
should be available during test execution.

Skipping decorators are not available in the nose python library,
therefore custom skipping decorator has to be made.

Partially implements blueprint: selenium-integration-testing

Change-Id: I6de4ec75ef9dc56f1ed11057d8b30bb0a782c6e3
Merge "Add test skip decorator when service not available"
Merge "Fix unexpected return from Step::__init__()"
Merge "Fix Volume DeleteBackup success message"