[1.5.0] Incorrectly List by Pypi as Available for Python < 3.7

`python_requires = >=3.4` should be updated as `python_requires =
>=3.7`, else Pypi will still list it as available for Python < 3.7.

Fixes sarugaku#61

Signed-off-by: Wong Hoi Sing Edison <hswong3i@pantarei-design.com>

setup.cfg

@@ -27,7 +27,7 @@ classifier =
 package_dir =
     = src
 packages = find:
-python_requires = >=3.4
+python_requires = >=3.7
 install_requires =
 zip_safe = true