Update ydiff version requirements

Author: avandras

requirements.txt

@@ -10,5 +10,5 @@ python-dateutil
 pysyncobj>=0.3.8
 cryptography>=1.4
 psutil>=2.0.0
-ydiff>=1.2.0
+ydiff>=1.2.0,<1.5,!=1.4.0,!=1.4.1
 python-json-logger>=2.0.2