Enable RSpec/HookArgument cop and fix issues

To be consistent about before/after arguments, as `:each` or `:example`
 are same and default scopes, best not to send an argument in those
 scenarios.

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

spec/shared/models/map_validations.rb

@@ -4,11 +4,11 @@ shared_examples "map validations" do
 
   describe "validations" do
 
-    before(:each) do
+    before do
       Setting["feature.map"] = true
     end
 
-    after(:each) do
+    after do
      Setting["feature.map"] = nil
     end