Update Keyboard Shortcuts

Keyboard-Shortcuts.md

@@ -33,4 +33,17 @@ Bouquin supports various keyboard shortcuts:
 - **Ctrl+.**: Set selected text to normal size (paragraph)
 - **Ctrl+Shift+-**: Decrease size of normal text
 - **Ctrl+Shift++**: Increase size of normal text
-- **Ctrl+`**: Set selected text to be in a ```<code>``` block
+- **Ctrl+`**: Set selected text to be in a ```<code>``` block
+
+
+### Checkboxes
+
+It's possible to add checkboxes into the editor.
+
+You can also start a line with the word TODO (in capitals) and it will automatically convert that word into a checkbox.
+
+#### Moving unchecked checkboxes from previous days
+
+Do you like to move any TODOs that were unfinished from yesterday to your list of today's TODOs?
+
+There is an option for that in the settings. When turned on, any unchecked checkboxes in the last 7 day's notes will be automatically moved to the next weekday after the last day's unchecked TODO. This occurs on startup or on rollover of midnight.