Now with static serving support

This version makes it much easier to render images from static local assets. Here's the gist:

--static/-s

The raster-eyes command now takes a --static (or -s) option that specifies where to serve up local assets:

raster-eyes --static .

This will internally add an express static handler so that URLs without the /raster-eyes/ prefix will be treated as static assets in the current working directory. Then it will redirect URIs in the form:

/{path}/{filename}

to:

/{path}/http://{hostname}:{port}/{filename}

which will capture a screenshot of your local assets as served through express. That means that if you have an index.html in the directory where you run raster-eyes --static ., you should be able to go to http://127.0.0.1/raster-eyes/index.html and see it rendered as an image.

Initial release

Huzzah!