Change endpoint URLs (close #154)

- styles at /style/{id}/style.json
- rendered tiles at /style/{id}/{z}/{x}/{y}.{format}
- TileJSONs at /style/{id}.json

src/serve_style.js

@@ -62,7 +62,7 @@ module.exports = function(options, repo, params, id, reportTiles, reportFont) {
 
   repo[id] = styleJSON;
 
-  app.get('/' + id + '.json', function(req, res, next) {
+  app.get('/' + id + '/style.json', function(req, res, next) {
     var fixUrl = function(url, opt_nokey, opt_nostyle) {
       if (!url || (typeof url !== 'string') || url.indexOf('local://') !== 0) {
         return url;