Add support for setting path

[nickbasham]

Unless specified, browsers will set a cookie's path to the current relative path. It would be great to either set the default path to root and/or allow the ability to set the path.

[cferdinandi]

This is probably overdone, but I just pushed a major version bump (now v1.x), that defaults to the root path, and supports an object of cookie options. Documentation updated to match.

[nickbasham-grayloon]

Awesome, thanks, Chris!