fix specs

enhance specs:
- be more specific when looking into validations
- don't add `nil` values to `children_chain` when looping and looking for loops in geographical area's relationships

Should fix random failures with travis (see PR #170)
Merge pull request #171 from bitzesty/revert_faraday

fix specs
Rename resource to control load order

http://guides.rubyonrails.org/configuring.html#using-initializer-files

"Initializer files are loaded in alphabetical order by their path."

In preview, redis_mutex.rb was being loaded before sidekiq.rb, and the
default redid config of 127.0.0.1:6379 was used, rather than the
intended values.