Fix template file inclusion in Python package (#731)

The setuptools documentation states that `package_data` is used for
finer-grained control over the inclusion of package data as an
alternative to `include_package_data`/`MANIFEST.in`. After correcting
the glob patterns in `package_data`, the latter mechanisms are no longer
needed.

setup.py

@@ -27,14 +27,13 @@
     packages=find_packages(exclude=['test', 'test.*']),
     package_data={
         'bloom.generators.debian': [
-            'bloom/generators/debian/templates/*',
-            'bloom/generators/debian/templates/source/*'
+            'templates/*/*',
+            'templates/*/source/*',
         ],
         'bloom.generators.rpm': [
-            'bloom/generators/rpm/templates/*'
-        ]
+            'templates/*/*.em',
+        ],
     },
-    include_package_data=True,
     install_requires=install_requires,
     extras_require={
         'test': [