function normalize(aPath) {
	  var path = aPath;
	  var url = urlParse(aPath);
	  if (url) {
	    if (!url.path) {
	      return aPath;
	    }
	    path = url.path;
	  }
	  var isAbsolute = exports.isAbsolute(path);

	  var parts = path.split(/\/+/);
	  for (var part, up = 0, i = parts.length - 1; i >= 0; i--) {
	    part = parts[i];
	    if (part === '.') {
	      parts.splice(i, 1);
	    } else if (part === '..') {
	      up++;
	    } else if (up > 0) {
	      if (part === '') {
	        // The first part is blank if the path is absolute. Trying to go
	        // above the root is a no-op. Therefore we can remove all '..' parts
	        // directly after the root.
	        parts.splice(i + 1, up);
	        up = 0;
	      } else {
	        parts.splice(i, 2);
	        up--;
	      }
	    }
	  }
	  path = parts.join('/');

	  if (path === '') {
	    path = isAbsolute ? '/' : '.';
	  }

	  if (url) {
	    url.path = path;
	    return urlGenerate(url);
	  }
	  return path;
	}
Normalizes a path, or the path portion of a URL:

- Replaces consecutive slashes with one slash.
- Removes unnecessary '.' parts.
- Removes unnecessary '<dir>/..' parts.

Based on code in the Node.js 'path' core module.

@param aPath The path or url to normalize.