Use Spring (new in Rails 4.1.0) as application preloader.

For more about it see:

http://edgeguides.rubyonrails.org/4_1_release_notes.html#spring-application-preloader
http://edgeguides.rubyonrails.org/upgrading_ruby_on_rails.html#spring
Moved secret_key_base for each environment to the (new in rails 4.1) secrets.yml file. This file is not uploaded to github.
Fix unit test.

The new feedjira version does not have the old bug in which xhtml content was wrapped in an extra div.