Monitoring plays are noncomformant to the rest of the plays

[cloudnull]

Presently monitoring does not use vars/repo_packages. The files required to setup monitoring to use the proper files has been created however the _raxmon_agentinstall role is not using any of the common roles to install packages or lay down base config.

Purposed changes:

• Remove package installation tasks from the _raxmon_agentinstall role.
• Remove apt repo add tasks from the _raxmon_agentinstall role.
• Remove git clone task from the _raxmon_agentinstall role.
• Remove pip install task from the _raxmon_agentinstall role.
• Remove raxmon_agent_key and raxmon_agent_repos from the group_vars/hosts.yml
• Convert the raxmon-setup.yml play to use vars/repo_packages.
• Include the _containercommon role in the raxmon-setup.yml play to facilitate package installation and basic configuration duties.
• Consider changing rackspace-monitoring and rackspace-monitoring-cli installation to be done in separate tasks
• Consider changing the installation process for rackspace-monitoring to use a source install from a given git sha. Presently these packages are being installed from the rackspace apt repo.

[mattt416]

Hi @cloudnull, would you mind giving this PR a once-over to ensure I'm on the right track? I did not leave the git-related variables in the repo_packages file as rcbops/rpc-maas does not have a setup.py and cannot be 'installed' with pip.