Catch client exception from nova in check_image
Catch client exception from nova in check_image

Ostf tests for check snapshots failed without
message if client excaption was happened
Catch exception and raise self.fail with descriptive message

Change-Id: I2845113577c8d057a3eaca5ce3bb18ee628a06a1
Closes-Bug: #1371051

stackforge/fuel-ostf,mcloudv/fuel-ostf,eayunstack/fuel-ostf,mcloudv/fuel-ostf,eayunstack/fuel-ostf,stackforge/fuel-ostf