Bugfixes and optimisations.

- Fix for __invoke methods (issue: #429)
- Fixed not being able to parse body of PUT request.
- BaseCsrfVerifier expects the field name to be "csrf-token" (issue: #432)
- Minor optimisations

src/Pecee/SimpleRouter/Router.php

@@ -188,7 +188,7 @@ class Router
             $this->routeStack = [];
 
             /* Route any routes added to the stack */
-            $this->processRoutes($stack, $route);
+            $this->processRoutes($stack, ($route instanceof IGroupRoute) ? $route : null);
         }
     }