Add new settings tab for participation processes

- Rename setting keys
- New tab por participation processes
- Hide these settings from features tab

spec/features/emails_spec.rb

@@ -380,7 +380,7 @@ feature "Emails" do
   context "Budgets" do
 
     background do
-      Setting["feature.budgets"] = true
+      Setting["process.budgets"] = true
     end
 
     let(:author)   { create(:user, :level_two) }