incoporating libsumo

[AboudyKreidieh]

libsumo is a feature in the latest versions of sumo that allow us to bypass some of the connection overhead when issuing traci calls.

What needs to be done:

• incorporate the newest version of sumo to master (close to done)
• build a docker image with new sumo (@fywu85 is working on this)
• test that new sumo does not cause our benchmarks to regress (for this we need regression tests, see Automated Regression Tests #30 )
• add libsumo installation to the setup instructions (this involves using cmake I believe)
• incorporate commands with libsumo -- a note here, libsumo does not allow us to use sumo's gui, which means we will need something like use_libsumo as an option from SumoParams at least temporary so that uses can train with libsumo and test/visulaize with traci
• monitor developments in sumo until the gui is working with libsumo, and modify the above things accordingly.

If I missed anything, feel free to add and discuss.

[AboudyKreidieh]

moving to #29