fixes #14913 - configure Hirb/Wirb via irbrc

Wirb 2.x can't be started before the IRB session itself, so use an irbrc
file per its docs to activate it and Hirb when starting a console.

fixes #15250 - ignore current controller from link_to/hash_for

When link_to generates a link on a page served from a nested controller
(e.g. foreman_example/examples) with a hash of controller/action from
our hash_for_*_path extension, it calls url_for which added the current...

Fixes #8797 - Separate style from the HTML in emails

By using roadie-rails gem (1.1) style can be separated from email
html foramt, and absolute paths can be used.
style was separated to 'email.css'

fixes #15040 - remove user fragment cache initializer

The initializer added in c3e0fed caused the foreman initializer to fail
as loaded the User model, which it assumes meant the table was present.
This isn't the case when db:migrate runs for the first time....

Fixes #12225 - invalidate topbar cache after restart

Fixes #14313 - improve facts navigation and URL

Refs #3809 - Turning on some rubocop cops

Fixes #14965 - turn off auditing during DB migrations

Move code turning off auditing during db:migrations so that it is
executed earlier than initializers

Fixes #6958 - supports in nested hostgroup in default PXE menu

The host group interface provides the opportunity to nest hostgroups,
with host groups inheriting parameters from parents.
when the default PXE menu is created however,
this nesting is not replicated, and only the final element...

fixes #14912 - setup console gems under bundler_ext