Fix style issues and revert some unrelated changes

.gitignore

@@ -15,5 +15,3 @@ examples/frameworks/pylonstest/pylonstest.egg-info/
 MANIFEST
 nohup.out
 setuptools-*
-.cache
-.eggs

docs/source/news.rst

@@ -2,10 +2,10 @@
 Changelog
 =========
 
-19.9.0 / 2018/05/26
+19.9.0 / not released
 ===================
 
-- the internal module `gunicorn.workers.async` was renamed to `gunicorn.workers.base_async`
+- The internal module ``gunicorn.workers.async`` was renamed to ``gunicorn.workers.base_async``
   since ``async`` is now a reserved word in Python 3.7
   (:pr:`1527`)
 

requirements_test.txt

@@ -1,3 +1,3 @@
 coverage>=4.0,<4.4  # TODO: https://github.com/benoitc/gunicorn/issues/1548
-pytest
-pytest-cov
+pytest==3.0.5
+pytest-cov==2.4.0