Update domdocument to allow fetching maps from meta

app/Dom/Document.php

@@ -42,6 +42,15 @@ class Document extends Node
 			}
 			return $values;
 		}
+		elseif ($node->isMap())
+		{
+			$values = [];
+			foreach ($node as $child)
+			{
+				$values[$child->getName()] = $child->getValue();
+			}
+			return $values;
+		}
 
 		throw new \Exception('Cannot retrieve meta value: '.$path);
 	}