add /_cat to list all of the other /_cat sub-endpoints

app.rb

@@ -417,6 +417,20 @@ get "/config", provides: "json" do
   jsonify config.as_json, pretty:
 end
 
+get "/_cat" do
+  stream do |out|
+    out << "=^.^=\n"
+    x = Sinatra::Application.routes.map do |method, route|
+      route.map do |route|
+        route.first.to_s
+      end
+    end
+    x.flatten.sort.uniq.each do |route|
+      out << "#{route}\n" if route.start_with? "/_cat"
+    end
+  end
+end
+
 get "/_cat/headers" do
   stream do |out|
     req_headers.each do |k, v|