Add support for puppetlabs-mysql 2.2

Puppetlabs-mysql has been rewritten to be much
cleaner. This patch adds a new parameter for the
nova mysql and init classes allowing users to use
the new version. Previous behavior will continue
as normal when using the old version (0.9)

Change-Id: I6d12a69180554348143f7f341f7570c52ecad140