dependencies: Add gunicorn

Adding gunicorn into the default environment so that we have it available when
dunning nix-shell as well.

pkgs/python-packages.nix

@@ -360,7 +360,7 b''
     };
   };
   certifi = super.buildPythonPackage {
-    name = "certifi-2016.02.28";
+    name = "certifi-2016.2.28";
     buildInputs = with self; [];
     doCheck = false;
     propagatedBuildInputs = with self; [];
@@ -1050,10 +1050,10 b''
     };
   };
   rhodecode-enterprise-ce = super.buildPythonPackage {
-    name = "rhodecode-enterprise-ce-4.0.0";
-    buildInputs = with self; [WebTest configobj cssselect flake8 lxml mock pytest pytest-runner pytest-cov];
+    name = "rhodecode-enterprise-ce-4.0.1";
+    buildInputs = with self; [WebTest configobj cssselect flake8 lxml mock pytest pytest-cov pytest-runner];
     doCheck = true;
-    propagatedBuildInputs = with self; [Babel Beaker FormEncode Mako Markdown MarkupSafe MySQL-python Paste PasteDeploy PasteScript Pygments Pylons Pyro4 Routes SQLAlchemy Tempita URLObject WebError WebHelpers WebHelpers2 WebOb WebTest Whoosh alembic amqplib anyjson appenlight-client authomatic backport-ipaddress celery colander decorator docutils infrae.cache ipython iso8601 kombu msgpack-python packaging psycopg2 pycrypto pycurl pyparsing pyramid pyramid-debugtoolbar pyramid-mako pyramid-beaker pysqlite python-dateutil python-ldap python-memcached python-pam recaptcha-client repoze.lru requests simplejson waitress zope.cachedescriptors psutil py-bcrypt];
+    propagatedBuildInputs = with self; [Babel Beaker FormEncode Mako Markdown MarkupSafe MySQL-python Paste PasteDeploy PasteScript Pygments Pylons Pyro4 Routes SQLAlchemy Tempita URLObject WebError WebHelpers WebHelpers2 WebOb WebTest Whoosh alembic amqplib anyjson appenlight-client authomatic backport-ipaddress celery colander decorator docutils gunicorn infrae.cache ipython iso8601 kombu msgpack-python packaging psycopg2 pycrypto pycurl pyparsing pyramid pyramid-debugtoolbar pyramid-mako pyramid-beaker pysqlite python-dateutil python-ldap python-memcached python-pam recaptcha-client repoze.lru requests simplejson waitress zope.cachedescriptors psutil py-bcrypt];
     src = ./.;
   };
   rhodecode-tools = super.buildPythonPackage {

setup.py

@@ -73,6 +73,7 b' requirements = ['
     'colander',
     'decorator',
     'docutils',
+    'gunicorn',
     'infrae.cache',
     'ipython',
     'iso8601',
@@ -114,6 +115,7 b' test_requirements = ['
     'lxml',
     'mock',
     'pytest',
+    'pytest-cov',
     'pytest-runner',
 ]