additional Cliudmade layers
add CloudMade 2X layers

These layers have bigger labels and main roads are thicker. As a result, these layers are good for devices with high-DPI screens or in case the user finds the normal text size too small.
add more CLoudMade layers
add Yandex maps, satellite and overlay
add new OSM layers, fix Public transport layer naming
add the Skobbler map layer based on OSM data
add MapQuest layers, bump revision