Add a RATP backend

[LCBH]

By fetching information from RATP, Vianavigo, http://www.transilien.com/ or whatever, we should write a backend that could answer to requests of the form:

ratp depa luxembourg             (next departures)
ratp depa luxembourg; orly       (next departures for a given direction)
ratp traf rer                    (trafic)
ratp traf metro
ratp itiner luxembourg; porte de vincennes  (roadmap)

We may use https://github.com/laurentb/weboob, https://github.com/pgrimaud/horaires-ratp-api or https://github.com/radium226/vianavigo.

[LCBH]

[Update] Take a look at OpenData Transilien, Data Sncf.
Maybe RailRadar would do the job: wiki (see their sources of data).
We could write a service dealing with both RATP and SNCF at once.

[LCBH]

Here is the best solution so far: http://www.navitia.io/