updates the release notes

distribution/ReleaseNotes.txt

@@ -1,12 +1,14 @@
 Release Notes
 
-HEAD, planned as v0.28
+v0.28, released on 13. September 2021
 - Inputs and outputs can have a smaller shape.
-- adds paste functionality to ROM data editor.
-- adds some more ATF150x devices
+- Added paste functionality to ROM data editor.
+- Added an rle encoding for storing rom content, which can
+  result in smaller dig files.
+- Added some more ATF150x devices
 - Probe is able to count edges.
 - Italian translation was added, special thanks to Luca Cavallari
-- adds a external component that is based on a file instead
+- Added an external component that is based on a file instead
   of storing the code in the component itself.
 - Fixed an issue with clicking on tightly placed components.
 - Allows variable sample size in default data graph.