Patched UsersHelper#user_settings_tabs to add a new Rates tab

* Wrapped UsersHelper#user_settings_tabs with an alias_method_chain
* Added the new Rate element to the return of user_settings_tabs
* Added RSpecs to confirm the change works without breaking
* Added a partial view for users/rates which will be used by Redmine
  when it renders the user edit panel

  #1913

lib/rate_users_helper_patch.rb

@@ -0,0 +1,24 @@
+require_dependency 'users_helper'
+
+module RateUsersHelperPatch
+  def self.included(base) # :nodoc:
+    base.send(:include, InstanceMethods)
+
+    base.class_eval do
+      alias_method_chain :user_settings_tabs, :rate_tab
+    end
+  end
+  
+  module InstanceMethods
+    # Adds a rates tab to the user administration page
+    def user_settings_tabs_with_rate_tab
+      tabs = user_settings_tabs_without_rate_tab
+      tabs << { :name => 'rates', :partial => 'users/rates', :label => :rate_label_rates}
+      return tabs
+    end
+    
+  end
+end
+
+UsersHelper.send(:include, RateUsersHelperPatch)
+