Plotting the Events done

There are subtle differences, the Cairo version looks
prettier - but that's fixable. I did a small triangle
and a exclamation mark on it. maybe a gradient would
make a good difference there.

this item has a ItemIgnoresTransformation tag, so
scalling, rotating or zooming will not change it's
size.

The tooltips are not yet ported.

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Finish the plotting of the events

Beautification of the triangles done, Tooltips are also displaying
Some rework on the code - don't know if dirk will accept, I'v changed
an if-else-if-else by a ternary operator, since it improves legibility
a little bit.

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Start populating the maintab Dive Info widget

Establish some useful helpers and use them when updating the values.

One of the helpers (from statistics.c) puzzlingly doesn't link - so that's
ifdefed out.

Also had to re-arrange the settings reading code (it came too late) and to
extract the expanding code of the top dive from the settings reading code
(as it had no business being there to begin with).

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>