pypiwin32 added to requirements

Signed-off-by: Joffrey F <joffrey@docker.com>

setup.py

 #!/usr/bin/env python
 import os
+import sys
+
 from setuptools import setup
 
+
 ROOT_DIR = os.path.dirname(__file__)
 SOURCE_DIR = os.path.join(ROOT_DIR)
 
@@ -11,6 +14,9 @@ requirements = [
     'websocket-client >= 0.32.0',
 ]
 
+if sys.platform == 'win32':
+    requirements.append('pypiwin32 >= 219')
+
 extras_require = {
     ':python_version < "3.5"': 'backports.ssl_match_hostname >= 3.5',
     ':python_version < "3.3"': 'ipaddress >= 1.0.16',

win32-requirements.txt

+-r requirements.txt
+pypiwin32==219
\ No newline at end of file