[Launch Instance Fix] Warn user if boot volume AZ differs from instance AZ

[Brian Tully]

In the new Launch Instance wizard, a user is able to select a bootable volume as a boot source. However we don't do any checks that prevent a user from selecting a bootable volume that resides in a different availability zone from the availability zone they have selected for the instance. For some deployments, this may be problematic. We do have help text in the help panel that says the following:

"If you select an availability zone and plan to use the boot from volume option, make sure that the availability zone you select for the instance is the same availability zone where your bootable volume resides."

However the UX could be improved to warn the user more directly. At the very least we should show the Availability Zone as a column header for volumes in the transfer table. Right now that information is not even visible.

If possible we should also add a warning icon and tooltip next to the volume's availabity zone name within the transfer table, and the tooltip would show the help text when hovering over the warning icon.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/168537

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/168537
Committed: https://git.openstack.org/cgit/openstack/horizon/commit/?id=8fe556965c46e30c422ea09eb8a3ebc79ecd190e
Submitter: Jenkins
Branch: master

commit 8fe556965c46e30c422ea09eb8a3ebc79ecd190e
Author: Brian Tully <email address hidden>
Date: Fri Mar 27 21:44:57 2015 -0400

    Warn if boot volume AZ differs from instance AZ

    For the Launch Instance source step, this patch adds the availability
    zone column to the transfer table when a volume is selected as a boot
    source. It also will display a warning icon next to the volume's AZ
    name if it differs than the selected instance AZ. When hovering over
    the warning icon it will reveal a toolip reminding the user to ensure
    the selected AZ is compatible with the volume AZ.

    Closes-Bug: 1437535
    Change-Id: I2f5f2672d976bfb274d7dfe22f455fd2cab823d5