Show total runtime on dive log list

[dylan-smith]

Probably do this by showing a time range. E.g.:

0:00 Start Dive
0:00 - 0:54 Descend to 18m
0:54 Switch Gas
0:54 - 1:54 Maintain Depth at 18m
1:54 - 3:42 Surface

Can maybe shorten the Maintain Depth items by moving the depth+time to the description.