Fixes #14645: fix production images for plugins.

Images were going through the legacy asset helpers in
sprockets-rails, this commit sets some options on the context
class to ensure we are looking up digested images in the correct
path.

http://projects.theforeman.org/issues/14645...

Fixes #12318 - support preview for deb-based distros

(cherry picked from commit 1bec6a3278483d7428760b1ab8b01bf65d3eead3)

Fixes #14508 - foreman-rake console can take arguments

One can now say e.g.

foreman-rake console -- --sandbox

We need the --, otherwise foreman-rake itself tries to interpret the flags

(cherry picked from commit d395b95185e2ef90a8661dac7d5cb1ea846585fe)

fixes #9782 - implement mediapath for suse/yast

(cherry picked from commit 7aa342eabf33f96916f3061db313aecba46b0933)

Fixes #14221: Use Sass Rails template when compiling plugin assets

The Sass::Rails::Template is needed to resolve css files imported
in an SCSS file without setting them to css imports which lead
to 404s in production.

(cherry picked from commit d8520a15230d854e65bb7de012a1a7e4f9806392)

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 #11059 - removing unused regexp_extensions file

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...

Refs #12911 - Fixing colon method calls