fixes #812 - new permissions model, user group role and nest support, role filters for better granularity

Contributions from:
* Daniel Lobato <elobatocs@gmail.com>
* Joseph Magen <jmagen@redhat.com>
* Tom McKay <thomasmckay@redhat.com>
* Greg Sutcliffe <gsutclif@redhat.com>
* Dominic Cleal <dcleal@redhat.com>
i18n - extracting new, updating rails, pulling from tx
Fixes #4536 - store fix_db_cache setting values correctly as YAML
Fixes #4226: add a Rake task for plugins that compiles their assets into core assets pipeline
fixes #4245 - return HTTP body for oVirt SSL CA certificate
fixes #3767 - add new host to hosts menu
fixes #4539 - changed os minor attribute to not required
Fixes #4353 - plugins don't create permissions until DB is migrated
fixes #3001 - Facts searchable by both host id and name
fixes #3163 - add link to first use instructions
fixes #4201 - update operating system by label, use description or fallname otherwise
Fixes #4553 - miscellaneous filters editing
fixes #4524 - The logged in user should be the default one in create new hosts
Fixes #4537 - user can set empty roles array via API
fixes #4290 add validation for user group max name length of 255
fixes #3996 Support to assign both cores and CPUs to VMWare guests
fixes #4442 - returning nil plays nice with try_to_login.
fixes #4194, #4459 - add main_app to root_path references for isolated engines
fixes #4583 - Added Environment name to rundeck output
fixes #3221 - add missing attributes to hostgroup show response