Add new settings tab for participation processes

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

spec/features/admin/budget_investments_spec.rb

@@ -19,11 +19,11 @@ feature "Admin budget investments" do
   context "Feature flag" do
 
     background do
-      Setting["feature.budgets"] = nil
+      Setting["process.budgets"] = nil
     end
 
     after do
-      Setting["feature.budgets"] = true
+      Setting["process.budgets"] = true
     end
 
     scenario "Disabled with a feature flag" do