Updated Changelog (markdown)

Changelog.md

@@ -12,7 +12,16 @@ This change log tracks the releases on our [pilot server](https://recodex.mff.cu
 Older versions are at the bottom of this page.
 
 ## 13.1.2020
-
+* Updating main results table on GroupDetail page to display interactive dialog when clicking on particular points.
+* New "reviewed" flag added to assignment solutions.
+* Implement new type of after submit notification concerning the reviewed flag.
+* Dialog for editing note of a solution.
+* Improving appearance of solution detail table by adding links to related solutions.
+* Adding (un)select all/invert selection features to RTE filter of the exercise list.
+* Code syntax highlighting added to markdown fields.
+* Many UX improvements (better labels, confirmation dialogs, buttons, shortcuts, missing info, styling...).
+* Switching from Symfony Yaml parser to PECL Yaml for performance reasons.
+* Entire API automatically reformatted by PHP Sniffer to PSR-12.
 
 ## 30.11.2019
 * User settings (notifications) updated, new notification added.
@@ -20,7 +29,6 @@ Older versions are at the bottom of this page.
 * Exercise tags implemented.
 * Bug fixes, English labels updated.
 
-
 ## 26.10.2019
 * Updates in SIS module -- supervisors may unbind a groups, students no longer see organizational groups.
 * Fixing bugs in error messages and their translations.