Add python_requires

Author: thombashi

setup.py

@@ -77,6 +77,7 @@ def get_release_command_class():
         "Tracker": "{:s}/issues".format(REPOSITORY_URL),
     },
 
+    python_requires=">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*",
     install_requires=SETUPTOOLS_REQUIRES + install_requires,
     setup_requires=SETUPTOOLS_REQUIRES + PYTEST_RUNNER_REQUIRES,
     tests_require=TESTS_REQUIRES,