Add support for registering a custom URLStreamHandler

[Horcrux7]

Because URL.setURLStreamHandlerFactory(x) can called only once this method can't use from an application inside of an application server.

Also the service loading via com.inet.lib.io.URLProtocolManagerURLStreamHandlerProvider does not work because the application is not on the root classpath.

There already different proprietary solution in different application servers for registering a custom URLStreamHandler.

There should be a standard solution.

It can be a method ServletContext like:

public void addURLStreamHandler( String protocol, URLStreamHandler handler )

or

public void addURLStreamHandlerFactory( URLStreamHandlerFactory factory )

There can be also an entry in the web.xml to register it declarative.

jakartaee/servlet#432

AB#73