fix amd property "hook" -> "actionHook" (#93)

markdown/docs/supporting-articles/answering-machine-detection.md

@@ -15,7 +15,7 @@ The answering machine detection feature can be enabled on outbound calls to prov
     }
   ],
   "amd": {
-    "hook": "/amdEvents"
+    "actionHook": "/amdEvents"
   }
 }
 ```

markdown/docs/webhooks/dial.md

@@ -13,7 +13,7 @@ The `dial` verb is used to create a new call by dialing out to a telephone numbe
     "method": "GET"
   },
   "amd": {
-    "hook": "/answeringMachineDetection",
+    "actionHook": "/answeringMachineDetection",
     "disconnectOnAMD": true,
 
   }