Fix broken requires

src/serve_rendered.js

@@ -15,7 +15,7 @@ var Canvas = require('canvas'),
     clone = require('clone'),
     Color = require('color'),
     express = require('express'),
-    mercator = new (require('sphericalmercator'))(),
+    mercator = new (require('@mapbox/sphericalmercator'))(),
     mbgl = require('mapbox-gl-native'),
     mbtiles = require('mbtiles'),
     pngquant = require('node-pngquant-native'),

src/server.js

@@ -12,7 +12,7 @@ var base64url = require('base64url'),
     cors = require('cors'),
     express = require('express'),
     handlebars = require('handlebars'),
-    mercator = new (require('sphericalmercator'))(),
+    mercator = new (require('@mapbox/sphericalmercator'))(),
     morgan = require('morgan');
 
 var packageJson = require('../package'),