.. now we've optimised out the model resets the diary window
(calendar chart) needs to explicitly repaint when a ride is
selected because the model won't reset unless the ride selected
is for a different month to the one currently shown.
.. example on the cover page of the manual
.. we need them to follow a naming convention
if section-keyword.pdf, e.g. 0-icon.pdf for
the icon on the title page (section 0).