MAINT: Refactor performance tracker as part of algorithm.

Instead of having the performance tracker as part of the
tradesimulation class, hold on to it inside of the algorithm
object, so that the perf_tracker is more easily accessed for
reset behavior, etc.
STY: Tweak comments in performance to match rest of file.
BUG: Ensure that order exists before attempting to cancel.
ENH: Support multi-day minutely emission.

Change the event loop so that minute emission has rollovers
between days.