(DRAFT) Added trip history mapping, fixed model evaluation

Implemented trip_history_to_system_states to generate data
for preliminary model evaluation. For proper model evaluation,
what we need is a large sequence of system states for
online validation.

TODO:
 - Fix API bugs
 - Write unit tests
 - Collect system state sequence data set by periodically sampling
 from the live station feed, so we can evaluate our CTMC model against
 a benchmark model