[Windows] Security model for files permissions - STEP 3a (#6964)

This PR implements the filesystem.chmod method from #6497.

* Implement filesystem.chmod

* Conditionally add pywin32 on setuptools versions that support environment markers.

* Update apache plugin requirements

* Use a try/except import approach similar to lock

* Add comments about well-known SIDs

* Add main command

* Call filesystem.chmod in tests, remove one test

* Add test for os module

* Update environment marker

* Ensure we are not building wheels using an old version of setuptools

* Added a link to list of NTFS rights

* Simplify sid comparison

* Enable coverage

* Sometimes, double-quote is the solution

* Add entrypoint

* Add unit tests to filesystem

* Resolve recursively the link, add doc

* Move imports to the top of the file

* Remove string conversion of the ACL, fix setup

* Ensure admins have all permissions

* Simplify dacl comparison

* Conditionally raise for windows temporary workaround

* Add a test to check filesystem.chown is protected against symlink loops

setup.py

@@ -3,7 +3,8 @@ import os
 import re
 import sys
 
-from setuptools import find_packages, setup
+from distutils.version import StrictVersion
+from setuptools import find_packages, setup, __version__ as setuptools_version
 from setuptools.command.test import test as TestCommand
 
 # Workaround for http://bugs.python.org/issue8876, see
@@ -52,6 +53,17 @@ install_requires = [
     'zope.interface',
 ]
 
+# Add pywin32 on Windows platforms to handle low-level system calls.
+# This dependency needs to be added using environment markers to avoid its installation on Linux.
+# However environment markers are supported only with setuptools >= 36.2.
+# So this dependency is not added for old Linux distributions with old setuptools,
+# in order to allow these systems to build certbot from sources.
+if StrictVersion(setuptools_version) >= StrictVersion('36.2'):
+    install_requires.append("pywin32 ; sys_platform == 'win32'")
+elif 'bdist_wheel' in sys.argv[1:]:
+    raise RuntimeError('Error, you are trying to build certbot wheels using an old version '
+                       'of setuptools. Version 36.2+ of setuptools is required.')
+
 dev_extras = [
     'astroid==1.6.5',
     'coverage',