[DRE-maint] ruby-rails-admin is marked for autoremoval from testing

[Debian testing autoremoval watch]

ruby-rails-admin 0.8.1+dfsg-2 is marked for autoremoval from testing on 2017-01-17

It (build-)depends on packages with these RC bugs:
846916: ruby-jquery-rails: provide jquery2: jquery3 breaks diaspora
846961: ruby-jquery-ui-rails: generate app directory using rake task