changelog: update for evolve 10.0.1

CHANGELOG

 Changelog
 =========
 
+10.0.1 - in progress
+--------------------
+
+  * compatibility with Mercurial 5.5
+
+  * evolve: update the template keywords section in `hg help -e evolve`
+
+  * obslog: make obslog --no-origin -f work with multiple successor sets
+
+topic (0.19.1)
+
+  * compatibility with Mercurial 5.5
+
 10.0.0 -- 2020-05-09
 --------------------