Fixes #3988 - use require instead of autoload_once_paths
Fixes #4515 - Add support for dynamic bindings
fixes #4256 - makes columns sortable in the UI
fixes #4664 - shorten OS description for SUSE
fixes #4669 - HostMailer summary method refers to undefined variable
fixes #4639 - array in lookup_value incorrectly displayed in form
fixes #4683 multi select filter and select/deselect all are not working
fixes #4138 orgs list when the number of orgs is huge
fixes #4682 - smart variable for a puppet class not showing in UI
fixes #4703 - reset_counters doesn't work for has_many :through relationships on rails 3.2.8
Usergroups can be linked to an LDAP auth_source. This allows usergroups
to be on sync with its equivalent LDAP usergroup.

Relation between auth_sources and usergroups

Tests, validations, and actual LDAP queries

Rake task to periodically refresh LDAP user groups

Adding LDAP users is done through User.where, not iterating through all possible users

Migration for groups/user OU, recursive usergroup search

Non recursive LDAP rake task

Check against LDAP aliases, or other empty results

Remove code from other branch

Remove Users OU because its irrelevant with Ldap_fluff

Ldap_fluff added to Gemfile

Refactor to use ldap_fluff and server type