fixes #18214 - accept `params` as AC::Parameters or Hash

In Rails 5, ActionController::Parameters no longer inherits from Hash
and so type checks for params.is_a?(Hash) now return false and should
accept either. (Rails commit 14a3bd5.)

fixes #18208 - replace audited-activerecord with audited (#4218)

Fixes #16752 - Extract template code from Host::Managed

Host::Managed contains a lot of code related with determining the
template that a host should have. Other Host objects such as
Host::Discovered might need that logic, without becoming a
Host::Managed....

fixes #18176 - replace clear_association_cache with reload

Reload is still necessary in Rails 5 as interfaces association will be
cached. The BMC test change is necessary to reload smart proxies
associated to the subnet after their features were altered - previously...

fixes #17545 - adds UI notification support

- Initial data model for notification support, based on manageiq design.
- addes notification JSON endpoints.

Fixes #10539 - Add default names for ifaces for oVirt CR VMs

Fixes #12547 - Added validators to interger fields

With this commit, instead of postgresql exception it will
show proper validation message for interger fields.

Fixes #17653 - Allow all parameters api to unhide values

Fixes #14714 - Make inherited Puppet Classes more apparent

To better recognize which Puppet Classes are inherited for Host
or Hostgroup they are under a sub-heading as a seperated list.

Fixes #3551 - Show unavailable Puppet Classes in Host Group edit

Puppet Classes can be assigned to a Host Group even if they are
not available in the set environment.

The Classes persist through out changes of the environment,
but were previously hidden from the UI this changes that....