Decoration button

This does not close, but mitigates issue #5 (closed) by improving documentation and the ability to see the key-point sequences.

doc/guide.rst

@@ -84,7 +84,7 @@ left-mouse button or trackpad click.
    to the desired location.
 
    To better visualize the order of keypoints, enable drawing of
-   ``Decorations`` by either click the check-button on the left pane or pushing
+   *Decorations* by either click the check-button on the left pane or pushing
    the keyboard key ``t``.