Reproject a TIFF into web mercator using node-gdal.
On the command line:
wmtiff [srcpath] [dstpath]
In node:
var wmtiff = require('wmtiff');
var path = require('path');
var srcpath = path.join('path', 'to', 'source', 'image');
var dstpath = path.join('path', 'to', 'destination', 'image');
wmtiff.reproject(srcpath, dstpath);