GRN2-176: Create a role editor that allows admins to specify what permissions each role has (#709)

* Add roles editor

* Add colour selection ability to roles

* Add ability to assign roles to users in the UI

* Remove rolify and replace it with our own custom roles implemenation

* - Fix all existing roles functionality
- Fix super admins

* Fix bugs with new customers not have default roles

* Add can't create room setting

* Code improvements

* Fix migration

* Add tests for new methods

* Translate reserved role names

* Pull roles from saml/ldap

* Fix rspec

* Fix scrutinizer issues

* Fix email promoted/demoted tests

* Apply comments

* Redirect directly to the main room

* Add comments

app/views/user_mailer/user_demoted.text.erb

@@ -17,9 +17,9 @@
 %>
 
 
-<%= t('mailer.user.demoted.subtitle') %>
+<%= t('mailer.user.demoted.subtitle', role: @role) %>
 
-<%= t('mailer.user.demoted.info', url: @url) %>
+<%= t('mailer.user.demoted.info', url: @url, role: @role) %>
 
 <%= t('mailer.user.demoted.more-info') %>