Exclude default ports 80/443 from base URL

[dinoboff]

Fix #59.

[dinoboff]

#getBaseUrl could use URL to parse the url, remove the search component and encode it again (URL by default remove the default ports).

We could import URL from whatwg-url and build a UMD version that expect global.URL.

@ddo would it be ok to use URL, to import whatwg-url on node and build the the browser version without the import (using window.URL) using something like rollup?

[dinoboff]

Actually it doesn't need a build process. With just one dep. and one file, it's no issue to manage the umd header manually.

[dinoboff]

Maybe URL is not suitable since it will normalise other components like unicode hostname.

To use URL, OAuth could throw if the provided URL is ambiguous.

[dinoboff]

closing: oauth-1.0a will need an other url parser.