Remove references to Python 3.4

Now that there exists only a gate job for Python 3.5 and not 3.4,
we should remove those references to the 3.4 that is untested.

Change-Id: I82f370a4d9da07e121e0ce6cac851008e3925639

setup.cfg

@@ -16,7 +16,6 @@ classifier =
     Programming Language :: Python :: 2
     Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.4
     Programming Language :: Python :: 3.5
 
 [files]

tox.ini

@@ -1,7 +1,7 @@
 [tox]
 minversion = 2.0
 skipsdist = True
-envlist = py35,py34,py27,pep8,releasenotes
+envlist = py35,py27,pep8,releasenotes
 
 [testenv]
 usedevelop = True