Right now, the code simply plots the first 30-second segment and ignores other ones.
We need this to change.
This requires changes to:
Timeline._draw_fork_events(), so we can peek ahead in the log file to see if there are multiple indexes per fork
Timeline._draw_fork_event() so we can determine the right width to plot the items
ForkLine, to draw a half (or a third) of a segment at the right start time and the correct width
Square, to draw half (or a third) of a segment at the right start time and the correct width for the sucessful/not successful indicators. As part of this I should refactor it so that success/not success is its own element.