Corrections for Ceilometer setup on Compute node

- Correct package and service names for RHEL/CentOS/Fedora.
- Use <systemitem class="service"> instead of <literal> for service names.
- Removed redundant os profiling condition (os was set on both step and
  the screen element within the step).

backport: havana
Change-Id: Ibb75b26c7b943db616c0a0d759e9f9826f5bb2f9
Corrected Ceilmeter installation for RHEL/CentOS/Fedora

Set correct package and service names for Ceilometer on RHEL, CentOS,
Fedora and derivative distributions.

Change-Id: I32e8fb4963739c2495b5e94c4eb87d0b8e920b97
backport: havana
Merge "Corrected Ceilmeter installation for RHEL/CentOS/Fedora"
Merge "Corrections for Ceilometer setup on Compute node"