REL: Release 0.5.2.

Fixes a bug in the `generate_files` utility where a non-notebook file in
the database would cause an exception.

Author: nathanwolfe

setup.py

@@ -23,7 +23,7 @@ def main():
 
     setup(
         name='pgcontents',
-        version='0.5.1',
+        version='0.5.2',
         description="A Postgres-backed ContentsManager for IPython/Jupyter.",
         long_description=long_description,
         author="Scott Sanderson",