v0.3.7: Remove windows classifiers since nobody tests this on windows

setup.py

@@ -3,7 +3,7 @@
 from setuptools import setup
 setup(
     name = 'python-mpv',
-    version = '0.3.6',
+    version = '0.3.7',
     py_modules = ['mpv'],
     description = 'A python interface to the mpv media player',
     url = 'https://github.com/jaseg/python-mpv',
@@ -17,12 +17,10 @@ setup(
         'multimedia'],
     classifiers = [
         'Development Status :: 4 - Beta',
-        'Environment :: Win32 (MS Windows)',
         'Environment :: X11 Applications',
         'Intended Audience :: Developers',
         'License :: OSI Approved :: GNU Affero General Public License v3 or later (AGPLv3+)',
         'Natural Language :: English',
-        'Operating System :: Microsoft :: Windows',
         'Operating System :: POSIX',
         'Programming Language :: C',
         'Programming Language :: Python :: 3.6',