Fix PEP 479/Python 3.7 incompatibility

Fixes #126
Adds 3.7 as travis testing target

Author: papr

.travis.yml

@@ -5,6 +5,7 @@ python:
   - "3.4"
   - "3.5"
   - "3.6"
+  - "3.7"
 
 matrix:
   include:

pyre/pyre.py

@@ -223,7 +223,6 @@ def recent_events(self):
         """Iterator that yields recent `PyreEvent`s"""
         while self.socket().get(zmq.EVENTS) & zmq.POLLIN:
             yield PyreEvent(self)
-        raise StopIteration()
 
     def events(self):
         """Iterator that yields `PyreEvent`s indefinitely"""