Fixes #14476 - Correctly handle casting of invalid real param values

(cherry picked from commit b953c6ae5390adb93e44c6778017373795c9bc63)

fixes #14096 - handle MiB style memory units on statistics page

(cherry picked from commit b24feca26d2f7b3f9bfb6a40680446ccebb3d44b)

Fixes #13725 - DHCP MAC conflicts are reported

(cherry picked from commit 4c9529c7bc3c081fb3d0bfdbee09b2e7d6eabc0a)

Fixes #13755 - allow reading of AR collections with safe mode enabled

Fixes #13557 - Rubocop enforce specifying a timezone

Rubocop can enforce what timezone to store in the database ,
so we can ensure everything is stored using UTC and we don't
miss these things in code reviews. When objects are displayed,
they must use the time provided by set_timezone in the...

fixes #13168 - permit safemode templates read-only access to AR relations

Templates such as kickstart_networking_setup use relations of
Host::Managed to access network interfaces. Since Rails 4, these return
relation objects rather than arrays which being core Ruby, had permitted...

fixes #13131 - plugin tests to skip is back

fixes #13039 - remove TemplateKind DB calls from UnattendedCtlr

UnattendedController created actions/methods during initialisation per
known TemplateKind, relying on the DB being populated. This caused
ordering issues when a plugin loaded the controller in a test...

Fixes #12754 - adds permission name to 403 page

Fixes #7230, #12021 - Upgrade to Rails 4.1.5

This commits upgrades Rails to Rails 4.1.5. See a description of the
changes included here, and go to the pull request in GitHub to see more
detailed explanations:

• Update gems to a Rails 4 compatible version, including dependencies...