Fix #61 - Add list of blocked users to the UI; clean up failed push notifications API

Try to fix Travis CI setup

spec/fabricators/device_fabricator.rb

@@ -1,3 +0,0 @@
-Fabricator(:device) do
-  registration_id "12345678"
-end

spec/lib/formatter_spec.rb

@@ -17,7 +17,7 @@ RSpec.describe Formatter do
     end
 
     it 'contains a link' do
-      expect(subject).to match('<a rel="nofollow noopener" target="_blank" href="http://google.com"><span class="invisible">http://</span><span class="ellipsis">google.com</span><span class="invisible"></span></a>')
+      expect(subject).to match('<a rel="nofollow noopener" target="_blank" href="http://google.com"><span class="invisible">http://</span><span class="">google.com</span><span class="invisible"></span></a>')
     end
   end
 

spec/models/device_spec.rb

@@ -1,5 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe Device, type: :model do
-
-end