Updating some core classes (Os, Dgram, etc..) and add some

Hello !

More updates ! I get in troubles with the method "resolve" of Path class. I can't find a way to do it, so I didn't modify it.

Same for Repl class, the extern is clearly outdated, but I don't understand documentation, with REPLServer, and node's source code for this class is clearly far away from documentation. So, I didn't modify it because I don't know what to do with it ^^

For others, everything seems to work!

Regards,
Peekmo