Added task to ensure that firewalld is running

A task has been added to ensure that firewalld is running before any
configuration changes are made. This should prevent issues associated
with editing firewalld configs when it is not running.
Merge pull request #60 from ausaccessfed/bugfix/firewalld-running

Added task to ensure that firewalld is running
Resolves #59
Merge branch 'develop' into feature/ldap-config