Windows support (complete!)

This is a fix for the Windows command line *and* jsdom issues.  Specifically:

* In the test script, using "node ./cli.js" instead of expecting cli.js to be executable on its own
* In the CLI, don't make *nix assumptions about paths (i.e., use path.resolve to test absolute path-ness, and don't assume that paths like "e:/foo" are URLs
* in the library, depend on jsdom-little (which doesn't use contextify) instead of jsdom, as html2jade doesn't actually use the parts of jsdom that need contextify.

With these changes "npm test" passes on Windows, at least for me.  Enjoy!