Add python_requires to help pip

setup.py

@@ -33,6 +33,7 @@ setup(name='jedi',
       keywords='python completion refactoring vim',
       long_description=readme,
       packages=find_packages(exclude=['test']),
+      python_requires='>=2.7, !=3.0.*, !=3.1.*, !=3.2.*',
       install_requires=install_requires,
       extras_require={'dev': ['docopt']},
       package_data={'jedi': ['evaluate/compiled/fake/*.pym']},