Fix: Fixed version of tinyrpc to not break the Ryu installation.

Change-Id: I901da179c43bdce4337575691fab82baae7987f4
Signed-off-by: peusterm <manuel.peuster@uni-paderborn.de>
diff --git a/setup.py b/setup.py
index 23bb860..c24498b 100755
--- a/setup.py
+++ b/setup.py
@@ -45,6 +45,7 @@
           'argparse',
           'networkx==1.11',
           'six>=1.9',
+          'tinyrpc==1.0.3',
           'ryu',
           'oslo.config',
           'pytest<=4.6.4',