pass id to ServerGroupsManager in ServerGroup.delete()

ServerGroup object delete currently fails because the manager object
requires the server group id and is instead passed the server group
object itself (copy-paste error). This patch changes it to pass the
id.

Change-Id: Ic6a4a38157f52343fbb3e75a02d1f7c6bef28d99
Closes-Bug: #1400494
Merge "pass id to ServerGroupsManager in ServerGroup.delete()"
novaclient sort parameters support

Adds sorting support to the 'nova list' command.

--sort <key>[:<direction>]

The --sort parameter is comma-separated and is used to specify
one or more sort keys and directions. The direction defaults to
'desc' for each sort key and the user can supply 'asc' to
override.

Partially implements: blueprint nova-pagination

Change-Id: I635e017c7f9ab61812333983bfecccd6fce8d394
Merge "novaclient sort parameters support"