No more of this find_packages nonsense.

Explicitly declare mediagoblin as the only package.  find_packages has
caused messes in the past :)

This commit sponsored by Pedro Ângelo.  Thanks!

setup.py

@@ -14,7 +14,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from setuptools import setup, find_packages
+from setuptools import setup
 import os
 import re
 
@@ -36,7 +36,7 @@ def get_version():
 setup(
     name="mediagoblin",
     version=get_version(),
-    packages=find_packages(exclude=['ez_setup', 'examples', 'tests']),
+    packages=['mediagoblin'],
     zip_safe=False,
     include_package_data = True,
     # scripts and dependencies