Docblock updates

Author: jpresutti

Deferred.php

@@ -30,7 +30,11 @@ public function __destruct()
             $this->deferredAction();
         }
     }
-    
+
+    /**
+     * Cancel this deferred call.
+     * @return void
+     */
     public final function cancelDeferral(): void
     {
         $this->cancelled = true;

HttpRequest/HttpRequest.php

@@ -520,13 +520,20 @@ public function getResponseAsXml(): ?SimpleXMLElement
 
     /**
      * Get the \Feast\Response object for a finished request.
+     * 
      * @return Response|null
      */
     public function getResponse(): ?Response
     {
         return $this->response;
     }
 
+    /**
+     * Get a response header by name.
+     * 
+     * @param string $name
+     * @return string|null
+     */
     public function getResponseHeader(string $name): ?string
     {
         if ($this->response === null) {
@@ -535,6 +542,10 @@ public function getResponseHeader(string $name): ?string
         return $this->response->getHeader($name);
     }
 
+    /**
+     * Get response content type.
+     * @return string|null
+     */
     public function getResponseContentType(): ?string
     {
         if ($this->response === null) {