Update 'Create Volume' button with ajax

This patch set makes button 'Create Volume (Quota Exceeded)'
be replaced with enabled button 'Create Volume' after
deleting a volume.

Closes-Bug: #1326589

Change-Id: I10ebc668f99ed3f502be07cb82759052a29654a1
Remove Cinder traces from test output (add missing mock)

Change-Id: If0191f56b7242a422198b7fed40ca342669dd211
Closes-Bug: #1340146
Merge "Update 'Create Volume' button with ajax"
Merge "Remove Cinder traces from test output (add missing mock)"