Upgrade python voltha-protos and pyvoltha in requirements.txt

Change-Id: I229be372f1e85511405a64c1dd1d68e0310e96ac
diff --git a/python/requirements.txt b/python/requirements.txt
index d6dd15d..c3ead8b 100644
--- a/python/requirements.txt
+++ b/python/requirements.txt
@@ -60,8 +60,8 @@
 etcd3==0.7.0
 pyparsing==2.2.0
 packaging==17.1
-pyvoltha==0.1.7
-voltha-protos==0.1.0
+pyvoltha==0.1.8
+voltha-protos==0.1.2
 
 # python-consul>=0.6.1  we need the pre-released version for now, because 0.6.1 does not
 # yet support Twisted. Once this is released, it will be the 0.6.2 version