command/revent: Fix resolver call

Call resolver's get() method, rather than get_resource(), incorrectly
introduced in the previous commit. Also add get() alias to the context
to allow it to be used as a resolver.

wa/commands/revent.py

@@ -292,4 +292,6 @@ class LightContext(object):
         self.resolver.load()
 
     def get_resource(self, resource, strict=True):
-        return self.resolver.get_resource(resource, strict)
+        return self.resolver.get(resource, strict)
+
+    get = get_resource