Disable gevent/greenlet for pypy.

.travis.yml

@@ -7,7 +7,7 @@ matrix:
     - python: "2.7"
       env: TEST_REQUIRE="gevent greenlet geventhttpclient fastimport"
     - python: "pypy"
-      env: TEST_REQUIRE="gevent greenlet geventhttpclient fastimport"
+      env: TEST_REQUIRE="fastimport"
     - python: "3.4"
       env: TEST_REQUIRE="gevent greenlet geventhttpclient fastimport"
     - python: "3.5"