specifying "lastest" as dep version in package.json is problematic

If this library requires the latest coffeescript, npm shrinkwrap fails like this:

    npm WARN unmet dependency /Users/plyons/projects/othenticate.com/node_modules/connect-coffee-script requires coffee-script@'latest' but will load
    npm WARN unmet dependency /Users/plyons/projects/othenticate.com/node_modules/coffee-script,
    npm WARN unmet dependency which is version 1.4.0

Changing that to a more liberal spec like "1.x" solves the problem.