refactor - various facts cleanups

FEATURE #982 API call to get fact keys

Signed-off-by: Corey Osman <corey@logicminds.biz>

fixes count vs size method on older ruby versions, refs #1045

fixes #1045 adds total memory usage chart to statistics page

Signed-off-by: Mikael Fridh <frimik@gmail.com>

take² fixes #893 fixed pagination issue in the facts page. fixed sort issue with out_of_sync, errors, active and disabled urls.

fixes #739: Clicking hostname leads to 'search', not details

fixes #831 - /hosts/fqdn/facts should not be a redirection

updated the JSON output as well to include leading hostname as root.

added search to facts page #refs 719

fixes #388 - added support to query inventory facts via json

fixes #302 and all references to_label and to_s
removed references to all per_page settings as they are common now

Fixes #212 - Remove AS from facts

fixes #231 - find_each LocalJumpError (no block given)

fixes #138 - Statistics page doesn't show any info if memory facts are unavailable

bug #99

fixes #89 - this adds basic graphs and charts for your inventory, it
also includes minor changes to the dashboard graphs

Adding Links to Audit Log
Currently Facts Auditing is disable

added act_as_audited plugin, seems to be a better implementation than our onws

added facts controllers

added fact models, aligned db schema with puppet schema, removed unneeded columns