Add key-chords to Readme

README.md

@@ -258,6 +258,14 @@ If you ever forget any of Projectile's keybindings just do a:
 
 <kbd>C-c p C-h</kbd>
 
+#### Key-chords
+
+Keybinding         | Description
+-------------------|----------------------------------------------
+<kbd>jj</kbd>      | ace-jump-mode
+<kbd>JJ</kbd>      | prelude-switch-to-previous-buffer
+<kbd>uu</kbd>      | undo-tree-visualize
+
 ### Automatic package installation
 
 The default Prelude installation comes with a bare minimum of