Enables RSpec/ExampleWording and fixes all issues

Both avoiding 'should' and repiting 'it' on the tests description
improves reading them and also makes all descriptions consistent.

Read about cop at http://www.rubydoc.info/gems/rubocop-rspec/RuboCop/Cop/RSpec/ExampleWording

spec/controllers/debates_controller_spec.rb

@@ -11,7 +11,7 @@ describe DebatesController do
       InvisibleCaptcha.timestamp_enabled = true
     end
 
-    it 'should create an ahoy event' do
+    it 'creates an ahoy event' do
 
       sign_in create(:user)
 
@@ -26,7 +26,7 @@ describe DebatesController do
       Setting['max_ratio_anon_votes_on_debates'] = 50
     end
 
-    it 'should allow vote if user is allowed' do
+    it 'allows vote if user is allowed' do
       Setting["max_ratio_anon_votes_on_debates"] = 100
       debate = create(:debate)
       sign_in create(:user)
@@ -36,7 +36,7 @@ describe DebatesController do
       end.to change { debate.reload.votes_for.size }.by(1)
     end
 
-    it 'should not allow vote if user is not allowed' do
+    it 'does not allow vote if user is not allowed' do
       Setting["max_ratio_anon_votes_on_debates"] = 0
       debate = create(:debate, cached_votes_total: 1000)
       sign_in create(:user)