Fix ceilometer.conf example source, Add preconf pipeline.yaml file

pipeline.yaml file (preconfigured example from github sources) needed for ceilometer v2013 services.

Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>
Fix pgrep -f for init scripts

Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>
Fix rabbit user for devstack site.pp example. Add Mysql::config before Mysql::db.

Default rabbit user for devstack is guest only. If any other used by site.pp, ceilometer services will fail to start.
Mysql config provides ~/.my.cnf file which must be created before mysql db provider issues any 'mysql -NBe' command, or it will fail with 'Using password: NO'.

Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>
Fix 'grant libvirt manage for libvirt group' is related to Centos case not Ubuntu.

Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>