Update Cirros to 0.3.2

Update Cirros image install to use newest version (0.3.2).

Change-Id: Ifedeec1c6660bde11c0833e2e50d3b316170fe76
Closes-Bug: #1301901
Remove unsupported --no-cache CLI parameter

Current versions of python-novaclient no longer support the --no-cache
option, and instead require a --os-cache option to use the cache.

Change-Id: Id0f11edbbdf0aaebc230346cb316b07d567a261b
Closes-Bug: #1302560
Merge "Update Cirros to 0.3.2"
Merge "Remove unsupported --no-cache CLI parameter"