Add database management support

database.yml is now managed by this module, and by default it will fully manage
a PostgreSQL server on the host.  The db_type parameter can be changed to
manage MySQL or use SQLite instead.  The puppet-postgresql and puppetlabs-mysql
modules are used.  db_manage can be changed to stop managing the server and
instead only manage Foreman's database config.
Add missing dependency on concat from file
Increase timeout to prevent failures
Merge pull request #6 from theforeman/master

Resync with theforeman's github