Dependent engines are required, but not dependencies of said engine
Dependent engines are required, but not dependencies of said engine

Followup to #1395

Basically, if you have an engine dependency, 1, in an app Gemfile,
it will be required and it's hooks would be added to the rails hooks.

If you add a second engine as a dependency, 2, as a dependency of the
first, 1, only 1 will be required.  You have to explicitly require 2
from 1.

https://bibwild.wordpress.com/2013/02/27/gem-depends-on-rails-engine-gem-gotcha-need-explicit-require/

ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic