889488 - run create user only if it is needed

addressing:
notice: /Stage[main]/Candlepin::Config/Postgres::Createuser[candlepin]/Exec[createuser-candlepin]/returns: executed successfully
notice: /Stage[main]/Katello::Config/Postgres::Createuser[katello]/Exec[createuser-katello]/returns: executed successfully
notice: /Stage[main]/Foreman::Config/Postgres::Createuser[foreman]/Exec[createuser-foreman]/returns: executed successfully
info: /Stage[main]/Foreman::Config/Postgres::Createuser[foreman]/Exec[createuser-foreman]: Scheduling refresh of Service[foreman
889488 - run createdb only if needed

addressing:
notice: /Stage[main]/Katello::Config/Postgres::Createdb[katellodb]/Exec[createdb-katellodb]/returns: executed successfully
notice: /Stage[main]/Foreman::Config/Postgres::Createdb[foreman]/Exec[createdb-foreman]/returns: executed successfully
info: /Stage[main]/Foreman::Config/Postgres::Createdb[foreman]/Exec[createdb-foreman]: Scheduling refresh of Service[foreman]
889488 - change selinux identity to system_u

addressing:
notice: /File[/var/log/foreman/thin-log.5500.log]/seluser: seluser changed 'unconfined_u' to 'system_u'
tee could not be used, because it is executed under postgres which does not have acl for /var/log/foo

addressing:
tee: /var/log/katello/katello-configure/create-postgresql-foreman-database.log: Permission denied
(cherry picked from commit 390730e7aa95d2a17453b9f7cb1cdf45b0a139bc)
Merge pull request #1353 from xsuchy/pull-req-bz889488

Bug 889488 - Katello-configure is not "stable"