[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

tox.cover.py

@@ -12,7 +12,7 @@ DEFAULT_PACKAGES = [
     'certbot_dns_sakuracloud', 'certbot_nginx', 'letshelp_certbot']
 
 COVER_THRESHOLDS = {
-    'certbot': {'linux': 98, 'windows': 93},
+    'certbot': {'linux': 97, 'windows': 96},
     'acme': {'linux': 100, 'windows': 99},
     'certbot_apache': {'linux': 100, 'windows': 100},
     'certbot_dns_cloudflare': {'linux': 98, 'windows': 98},