Missing catch InstanceNotFound in v3 API

After apply instance look helper, some compute api
will invoke instance.save(), it will raise
InstanceNotFound also.
This patch adds them.

Closes-Bug: #1280067
Change-Id: I73cb35c90f1e46a447ae1807a997713105e08bde
Imported Translations from Transifex

Change-Id: Id0019f3420f4a2965fb293b0fd04062fc0e807d0
Merge "Missing catch InstanceNotFound in v3 API"