WIP- Merging back my ansible-mesos fork.

I forked ansible-mesos and https://github.com/mhamrah/ansible-marathon some time ago, and I wanted to get these branches back in sync so we can team up on this role. This PR is to give you an FYI and receive feedback for the merge. I noticed @kienpham2000 was making similar changes, and figured why duplicate. 

Major changes:

* Version 0.20.1 of mesos
* Containerizer is docker,mesos by default
* Provide a deconstructed zookeeper/mesos master url so a playbook can easily create a master cluster based on ```groupvars```
* RedHat family support (issues with zookeeper installation)
* Sourced environment variables for settings, as per Mesos documentation.

Let me know what you think.
I noticed the docker-support flag earlier. I can go either way, but I
personally believe roles should be the lowest-common-denominator with
playbooks allowing build-up of installed services. My vote would be to
separate out the mesos installation and configuration from docker
installation. Ansible-docker can supply the docker support. You also only
need docker support on the slaves which increases the variables required
for users if we included this with ansible-mesos: do you want it installed
everywhere or just the slaves? What if you want slaves and masters to have
different docker support?

The only thing mesos needs to know about docker is setting the
containerizers path, which I think is where this role should also begin and
end. I add ansible-docker as a role in my mesos-playbook and like the
layering the discrete components provides:
https://github.com/mhamrah/ansible-mesos-playbook/blob/master/playbook.yml#L40

Mike

On Mon, Oct 27, 2014 at 11:29 AM, Kien Pham <notifications@github.com>
wrote:

> In vars/main.yml:
>
> >
> > -mesos_arch: "amd64" # alt for >= 13.10 is facter_architecture
> > -mesos_file_name: "mesos_{{mesos_version}}_{{mesos_arch}}.{{package_type}}"
> > -mesos_dest_file: "/tmp/{{mesos_file_name}}"
> > -
> > -platform_url_name: "ubuntu"
> > -package_type: "deb"
> > +# Containerizer
> > +mesos_containerizers: "mesos"
>
> I actually have docker_support flag in the upstream repo already:
>
> https://github.com/AnsibleShipyard/ansible-mesos/blob/cd0e5dd550d602ff7875623301dfaa288d421107/tasks/slave.yml#L9
>
> If you think this is better, then we should remove docker_support flag.
> Also if people want to use docker, this PR doesn't install the docker for
> them? I think it should since that's what people would expect. I'm
> currently doing it already at the upstream level. Also please pull the
> latest upstream into your PR to resolve conflict. I can't merge it now.
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/AnsibleShipyard/ansible-mesos/pull/16/files#r19412166>
> .
>