Don't use six when testing httplib

Otherwise monkeypatching get confused and will not work
and the tests will fail. An effort was made to use the
six http_client always (both in tests and the interceptor)
but this led to infinite recursion, so going for the lame
fix here.

The functionality has always worked (as long as six wasn't
involved) this is just getting things working in tests.

test/test_interceptor.py

@@ -11,7 +11,11 @@ import py.test
 import requests
 import urllib3
 from httplib2 import Http, ServerNotFoundError
-from six.moves import http_client
+# don't use six as the monkey patching gets confused
+try:
+    import http.client as http_client
+except ImportError:
+    import httplib as http_client
 from six.moves.urllib.request import urlopen
 from six.moves.urllib.error import URLError
 

wsgi_intercept/http_client_intercept.py

@@ -19,16 +19,13 @@ except ImportError:
             HTTPSConnection as OriginalHTTPSConnection
     )
 
-HTTPInterceptorMixin = WSGI_HTTPConnection
-HTTPSInterceptorMixin = WSGI_HTTPSConnection
 
-
-class HTTP_WSGIInterceptor(HTTPInterceptorMixin, http_lib.HTTPConnection):
+class HTTP_WSGIInterceptor(WSGI_HTTPConnection, http_lib.HTTPConnection):
     pass
 
 
-class HTTPS_WSGIInterceptor(HTTPSInterceptorMixin, http_lib.HTTPSConnection,
-        HTTP_WSGIInterceptor):
+class HTTPS_WSGIInterceptor(WSGI_HTTPSConnection, http_lib.HTTPSConnection,
+                            HTTP_WSGIInterceptor):
 
     def __init__(self, host, **kwargs):
         self.host = host