Bounding box JSON

@mborodenko here some feedback to the current bounding box and map implementation:

Values must be treated as numbers (not string):

{
	"west": "47.274719",
	"south": "5.86416600000001",
	"east": "55.056664",
	"north": "15.0388869999999"
}

And labels must correspond to:

1. west is minLongitude
2. east is maxLongitude
3. north is maxLatitude
4. south is minLatitude

Please update map-centering javascript code for the map.