groups: section should support group id

This bug was originally filed in Launchpad as [LP: #1075769](https://bugs.launchpad.net/cloud-init/+bug/1075769)

Launchpad details

affected_projects = []

assignee = harlowja

assignee_name = Joshua Harlow

date_closed = None

date_created = 2012-11-06T22:54:30.963176+00:00

date_fix_committed = None

date_fix_released = None

id = 1075769

importance = medium

is_complete = False

lp_url = https://bugs.launchpad.net/cloud-init/+bug/1075769

milestone = None

owner = alex-guan

owner_name = Alex Guan

private = False

status = triaged

submitter = alex-guan

submitter_name = Alex Guan

tags = []

duplicates = []

_Launchpad user **Alex Guan(alex-guan)** wrote on 2012-11-06T22:54:30.963176+00:00_

We need to be able to specify the group id when adding a group via groups: direction in cloud-config section