Tell npm 1.2.24 to install.
It looks like npm 1.2.24 (bundled with node 0.8.24) doesn't run wscripts by default.
0.5.5
Add test for a vector tile source.
Skip mask decoding/checking for PBF format tilesources.
0.5.6
remove old node-waf reference, letting npm auto-find binding.gyp