Reset graph doesn't hold up through history changes

[glacials]

Seems to be very similar to #278, but the root cause is different.

When a segment is added, removed, or has its history cleared (e.g. by clearing the gold time in LiveSplit, which also clears all history), the Resets Per Split graph stops being accurate -- it starts to think that the split before the one you changed had a bunch of resets, because it can't trace runs through both splits anymore.

i.e.

a -> b -> c -> d # a completed run looks like this
a -> b -> c      # this run was reset during the c segment (before the c/d split)
> runner deletes c's history
> now all past runs look like
a -> b
> so we think b has a ton of resets

We should make this graph match the one above it, which tracks resets based on completed attempts vs. non-completed attempts.