Install quantum packages before doing anything else

We need the basic quantum packages to have quantum-rootwrap and the
quantum services installed, before we do the rest. Otherwise, the first
chef-client run will fail because other recipe will try to access these
resources that don't exist yet.

Example of failure:

[Sun, 16 Jun 2013 13:13:57 +0000] INFO: Processing service[openstack-quantum]
action restart (quantum::server line 186)

================================================================================
Error executing action `restart` on resource 'service[openstack-quantum]'
================================================================================

Mixlib::ShellOut::ShellCommandFailed
------------------------------------
Expected process to exit with [0], but received '1'
---- Begin output of /sbin/service openstack-quantum restart ----
STDOUT:
STDERR: service: no such service openstack-quantum
---- End output of /sbin/service openstack-quantum restart ----
Ran /sbin/service openstack-quantum restart returned 1
Merge pull request #53 from vuntz/install-package-first

Install quantum packages before doing anything else