Fix AttributeError in VolumeSnapshot

This fixes a regression introduced in
Hiding "Launch as Instance" if volume is not bootable.

Change-Id: I9c45a1f5f4e3a096843ba6547dbf76387501f447
Closes-Bug: 1368732
Imported Translations from Transifex

Change-Id: I662d791a53f17ea92e91d794f96a36d3f9e784ae
Use integer instead of string for form max_length

This is a follow-up patch of a comment
in https://review.openstack.org/#/c/119134/

Change-Id: I87f0a5698e5ccde251eb9cd9c1280291f5d746e0
Merge "Fix AttributeError in VolumeSnapshot"
Merge "Use integer instead of string for form max_length"
Merge "Imported Translations from Transifex"
Merge branch 'master' of https://github.com/openstack/horizon