[#2488] Update with 0.82.

Problem
======

A new release of watchdog is available.
It contains a fix for cleaning the windows directory on close.


Changes
=======

Merge upstream master with our forked master and update the code to use the latest changes on upstrea,

The windows bugfix is in src/watchdog/observers/winapi.py and it is from upstream.

How to test
=========

reviewers: @alibotean 

this is mainly to let you know about the changes. All current changes are done because they were done upstream so there is not much we can change.

Some of the changes form upstream were triggered by my pull requests but upstream developer has a different programming style so he solved the problem by rewriting the code...but I am happy with his changes.
 this is another reason why diff is big

We will need Laura to check that one integrated with server it works.

Thanks!

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this is upstream... I have removed it hoping that upstream will also remove it, but it is still there.
for /tests i prefer to keep the code as upstream.

Note that /tests will not work as our watchdog has some changes...ie, not emit change event for all changes.