update pypi classifier to Production / Stable

setup.py

@@ -62,7 +62,7 @@ setup(
     license='BSD',
     long_description=open('README.rst').read(),
     classifiers=[
-        'Development Status :: 4 - Beta',
+        'Development Status :: 5 - Production/Stable',
         'Environment :: Web Environment',
         'Intended Audience :: Developers',
         'License :: OSI Approved :: BSD License',