Bug 1143565: Bump marionette driver to v 0.3.1; r=chmanchester

--HG--
extra : rebase_source : ba132e5ac13888582297e06097aa1531f5c72c11

testing/marionette/driver/setup.py

@@ -1,6 +1,6 @@
 from setuptools import setup, find_packages
 
-version = '0.2'
+version = '0.3.1'
 
 # dependencies
 with open('requirements.txt') as f: