add dependcies

Author: dkrnl

composer.json

@@ -14,6 +14,9 @@
     },
     "license": "Public Domain",
     "require": {
-        "php": ">=5.3.0"
+        "php": ">=5.3.0",
+        "lib-libxml" : "*",
+        "ext-xmlreader" : "*",
+        "ext-dom" : "*"
     }
 }