Multi distro installation support

Now the playbook is able to install Ceph on RedHat systems.
This has been tested on CentOS 6.

Signed-off-by: Sébastien Han <sebastien.han@enovance.com>
Merge pull request #13 from leseb/wip-support-install-rh

Multi distro installation support
Use full device name

Use full device name so we can specify custom devices (by-path, links
etc...)

Closes: #17

Signed-off-by: Sébastien Han <sebastien.han@enovance.com>
Allow to disable MDS

Even if MDS are not configured in site.yml the playbook has a
dependancy on the ceph.conf template.
This disables the mds section from the ceph.conf file.

Closes: #21

Signed-off-by: Sébastien Han <sebastien.han@enovance.com>
Remove hardcoded interface name

Add the ability to select a binding interface for the monitors.

Closes: #20

Signed-off-by: Sébastien Han <sebastien.han@enovance.com>
Merge pull request #23 from leseb/fix-hardcoded-eth

Remove hardcoded interface name
Merge pull request #22 from leseb/fix-allow-disable-mds

Allow to disable MDS
Merge pull request #18 from leseb/fix-rm-dev

Use full device name
Autogenerate initial mon key

As mentionned in the issue 24 it's not really safe to store a default
fsid nor a monitor key. Thus the commit brings the auto-generation of
the initial monitor key. However it is quite complex to do the same for
the fsid, so I leave this to the person in charge of the deployment to
generate one and edit group_vars/all accordingly. The default fsid has
been removed as well.

Close: #24

Signed-off-by: Sébastien Han <sebastien.han@enovance.com>
Merge pull request #25 from leseb/fix-gen-keys

Autogenerate initial mon key
Separate OSD scenarios to multiple files

Currently everything lives in main.yml, the file has become difficult to
read at some point and can be a real mess since we keep adding new
scenarios.
I think we should separate the scenarios into dedicated files and just
do includes in the main.yml file.

Closes: #16

Signed-off-by: Sébastien Han <sebastien.han@enovance.com>
Merge pull request #26 from leseb/wip-separate-osd-scenarios

Wip separate osd scenarios