update to readme

README.md

@@ -36,7 +36,7 @@ A class can be registered with objection using the macros *objection_register* o
 
 ### Fetching Objects from Objection
 
-An object can be fetched from objection by creating an injector and then asking for an instance of a particular class. An injector manages its own object context. Which means that a singleton is per injector and is not necessarily a *true* singleton.
+An object can be fetched from objection by creating an injector and then asking for an instance of a particular class or protocol. An injector manages its own object context. Which means that a singleton is per injector and is not necessarily a *true* singleton.
 
     - (void)someMethod {
       ObjectionInjector *injector = [Objection createInjector];