Include additional classifiers

I've included Python 2/3 as they are not parent classifiers but
sibling classifiers. They denote that this project will work with
*some* versions of python and by having them, they'll show up for
people searching for python 2 or 3 projects.

According to the internet :)

Signed-off-by: Mazz Mosley <[email protected]>

setup.py

@@ -67,7 +67,13 @@ setup(
     docker-compose=compose.cli.main:main
     """,
     classifiers=[
+        'Development Status :: 5 - Production/Stable',
+        'Environment :: Console',
+        'Intended Audience :: Developers',
+        'License :: OSI Approved :: Apache Software License',
+        'Programming Language :: Python :: 2',
         'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3',
         'Programming Language :: Python :: 3.4',
     ],
 )