Update travel type mechanism

[gerbsen]

Currently we can only set one single travel type per request. Also all other parameters depending on a certain travel type can only be set once like bikeUphill and not individually per source. The RequestConfigurator is also over-engineered an could just use JSON serialisation libraries like jackson.

{
  'tm' :  {
    'car' : {
      'rushHour' : true
    }
    // or
    'walk' : {
      'walkSpeed' : 6,
      'walkUphill' : 6,
      'walkDownhill' : 6
    }
    // or
   'transit' : {
      "frame": {
	"time": 58500,
        "date": "20171213",
	"duration": 18000
     }
   }
 }

[gerbsen]

the frame property also does not make sense and should be deprecated and removed in the backend, for a transitioning period we are gonna need both

[DavidRedlich]

also for RequestConfigurator:
setting parameters for BIKE_TRANSIT, WALK_TRANSIT are missing
recommendations are set for all travelModes not just for the transit types

[gerbsen]

BIKE_TRANSIT is not supported anymore, walk_transit is basically transit. recommendations do only make sense/are possible for transit as of 13.12.2017