Style network address for subnet as required field

It does this by adding the required class to the network address field when the
checkbox is enabled.

I have also made the checkbox behave like a switchable select so when the create
subnet checkbox is checked all fields are visible. They are hidden when create
subnet is unselected.

When the checkbox is disabled the 'subnet details' step in the workflow is
hidden and the workflow can finish there by clicking the create button as all
other information is to do with subnet creation.

Issue highlighted in bug #1371901 was caused by the select.switchable methods in
horizon.forms.js looking at everything with class switchable instead of only
looking at select objects with class switchable.

Change-Id: I92d7b5eee758f0433e3fb61704ddb82f52147ad5
Closes-bug: 1367858
Related-bug: 1371901
Hide gateway ip input field if gateway ip disabled

If the checkbox for gateway ip is selected, meaning that a gateway ip should not
be set, then hide the gateway ip input field.

Change-Id: I8f3764aeb30225e2cfcdd97d661ab4bbb9b173f8
Closes-bug: 1372313
Make timezones translatable

Use timezone info in Babel to translate timezones.  Sort
timezones by offset.  Update format to:
    UTC -06:00: United States (Chicago) Time

Thanks amotoki for suggesting to use Babel to handle this!

Not updating environment_version in run_tests.sh because Babel isn't
a new requirement; it's just being made explicit.

Change-Id: I15d39b94d441e9e155870a0593d11e67e68f9bd9
Closes-Bug: #1333927
Show domain name in the change project dropdown

When the OPENSTACK_KEYSTONE_MULTIDOMAIN_SUPPORT is enabled, the
domain's UUID  is being shown in the dropdown to change project.
This patch corrects it to show the domain's name.

Change-Id: I7719d615f736f9d36c305a48f8b4caecb4d0c4ca
Closes-bug: 1378034
Merge "Style network address for subnet as required field"
Merge "Hide gateway ip input field if gateway ip disabled"
Merge "Show domain name in the change project dropdown"
Merge "Make timezones translatable"