Release 2.0.0

Update version number and update documentation

* Support XDG base directory specification
* Redesign alternate processing
* Add built-in default template processor
* Allow storing alternates in yadm dir (#90)
* Add support for j2cli template processor
* Ignore encrypted files (#69)
* Support DISTRO in alternates (#72)
* Support `source` in templates (#163)
* Change yadm.cygwin-copy to yadm.alt-copy
* Support `-b <branch>` when cloning (#133)
* Support includes for j2-based templates (#114)
* Remove stale/invalid linked alternates (#65)
* Add support for Mingw/Msys (#102)
* Allow `-l` to pass thru to the `yadm config` command
* Improve processing of `yadm/encrypt`
* Fix bugs in legacy alternate processing
* Fix bug with hidden private files
* Improve support for older versions of Git
* Add upgrade command

CONTRIBUTORS

@@ -3,15 +3,19 @@ CONTRIBUTORS
 Tim Byrne
 Espen Henriksen
 Cameron Eagans
+Ross Smith II
 Klas Mellbourn
 Jan Schulz
+Satoshi Ohki
 Siôn Le Roux
 Sébastien Gross
 Thomas Luzat
 Tomas Cernaj
 Uroš Golja
+Brayden Banks
 japm48
+Daniel Wagenknecht
 Franciszek Madej
+Mateusz Piotrowski
 Paraplegic Racehorse
 Patrick Hof
-Satoshi Ohki