Update changelog

CHANGELOG.md

@@ -9,6 +9,7 @@
 - Updated StatusController, restrict edits to 24 hours ([ae24433b](https://github.com/pixelfed/pixelfed/commit/ae24433b))
 - Updated RateLimit, add max post edits per hour and day ([51fbfcdc](https://github.com/pixelfed/pixelfed/commit/51fbfcdc))
 - Updated Timeline.vue, move announcements from sidebar to top of timeline ([228f5044](https://github.com/pixelfed/pixelfed/commit/228f5044))
+- Updated lexer autolinker and extractor, add support for mentioned usernames containing dashes, periods and underscore characters ([f911c96d](https://github.com/pixelfed/pixelfed/commit/f911c96d))
 
 ## [v0.10.8 (2020-01-29)](https://github.com/pixelfed/pixelfed/compare/v0.10.7...v0.10.8)
 ### Added