Fail when ssl parameters are missing and rabbit_use_ssl is set to true

This commit causes the run to fail is rabbit_use_ssl parameter is set
to true but the ssl related parameters remains undef.

Change-Id: Idd40601fe4a632204fdde120b857d0e22b6a2aed
(cherry picked from commit 55cbdace1730a3cb0af780ab9f7be703ac873eab)
Makes kombu_ssl_* parameters optional when rabbit_use_ssl => true

The kombu_ssl_* parameters should not be required when rabbit_use_ssl => true
Rather, rabbit_use_ssl must be set to true if the kombu_ssl_* parameters are
used.

Change-Id: I7664dda2c66ffb34ceb56ada722574ae0e490f8f
Closes-Bug: 1356083
(cherry picked from commit 957c2120d0ee0b9db08bfddcce996686ba61d97d)
Ensure nova-common is installed before ceilometer

Ceilometer depends on the nova user and group being
present. This change adds a dependency to nova-common
to ensure that packging will handle the user before
the ceilometer compute agent tries to add user ceilometer
to the nova group.

Fixes bug 1350980

(cherry picked from commit 08fc9d9159cd9eb0830d550abb1058bc2b9b5759)

Conflicts:
	spec/classes/ceilometer_agent_compute_spec.rb

Change-Id: I26dd4e8e4172d777a04d99c7d23c1861714ca079
Merge "Ensure nova-common is installed before ceilometer" into stable/icehouse