fixes requirements/dev.txt

requirements/dev.txt

@@ -1,3 +1,3 @@
-https://github.com/celery/billiard/zipball/master
-https://github.com/celery/kombu/zipball/master
-https://github.com/celery/celery/zipball/master
+https://github.com/celery/py-amqp/zipball/master#egg=amqp
+https://github.com/celery/billiard/zipball/master#egg=billiard
+https://github.com/celery/kombu/zipball/master#egg=kombu