Bump the version to v0.5.2

Author: 1st1

setup.py

@@ -15,7 +15,7 @@
 
 setuptools.setup(
     name='asyncpg',
-    version='0.5.1',
+    version='0.5.2',
     description='An asyncio PosgtreSQL driver',
     classifiers=[
         'License :: OSI Approved :: Apache Software License',