reqs: use packaged python-etcd

After updating our apt-get cache, using the fix in our vendored version
is no longer necessary.

requirements-nover.txt

@@ -38,7 +38,6 @@ git+https://github.com/DevTable/aniso8601-fake.git
 git+https://github.com/DevTable/anunidecode.git
 git+https://github.com/DevTable/pygithub.git
 git+https://github.com/DevTable/container-cloud-config.git
-git+https://github.com/DevTable/python-etcd.git@sslfix
 git+https://github.com/coreos/peewee.git
 git+https://github.com/coreos/py-bitbucket.git
 git+https://github.com/coreos/pyapi-gitlab.git
@@ -53,4 +52,5 @@ stringscore
 python-swiftclient
 python-keystoneclient
 Flask-Testing
-pyjwt
+pyjwt
+python-etcd