WIP Node Platform - Add support for settable user variables

* Update Openshift mcollective agent and ddl
* Move gear ssh key creation to happen when gear created
* Added oo-user-var-add/remove/list commands
* Create .env/user_vars when creating gear

Bug 988759 - Failed to override the existing variables
Bug 988691 - Failed to add the 25th user variables
User vars node changes:
 - Use 'user-var-add' mcollective call for *add* and/or *push* user vars. This will reduce unnecessary additional code/complexity.
 - Add some more reserved var names: PATH, IFS, USER, SHELL, HOSTNAME, LOGNAME
 - Do not attempt rsync when .env/user_vars dir is empty
 - Misc bug fixes
Added User environment variables support in broker

Use x.present? instead of (not x.nil? and  not x.empty?)
Added REST api support for user environment variables