small config fix

Author: Faustasm

setup.cfg

@@ -11,7 +11,7 @@ packages=['upcloud_api', 'upcloud_api.cloud_manager']
 license = MIT
 
 [options]
-python_requires = >=3.6
+python_requires = >=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*, <4
 setup_requires =
     setuptools
     pytest-runner