Bust first search implemented

Added two new commands.

* bus <search_param>
  - Example: "bus kendall cruiser"
  - Returns: "288 - Kendall Cruiser"
* bus <search_param> at <stop_id>
  - Example: "bus 101 at 2884"
  - Returns: "Arrives at 20.23 mins, 53.00 mins, 84.34 mins"

Note that the search is flaky when it comes to letter buses like A or S. Better to publicize the numbers & names rather than letters". If the search finds more than 1 result, the first one is returned.