Add changelog entry.

CHANGELOG

 Please view this file on the master branch, on stable branches it's out of date.
 
 v 7.10.0 (unreleased)
+  - Fix generating SSH key fingerprints with OpenSSH 6.8. (Sašo Stanovnik)
   - Include missing events and fix save functionality in admin service template settings form (Stan Hu)
   - Fix "Import projects from" button to show the correct instructions (Stan Hu)
   - Fix dots in Wiki slugs causing errors (Stan Hu)