RFR JDK-8066867: Add InputStream transferTo to transfer content to an OutputStream

[Pavel Rappo]

> In the transferTo then transferred needs to be a long.

> „transferred“  should be a long instead of int

Good catch, guys!

> ...the method names are inconsistent (the methods in lower case with embedded underscores)

Fixed. Updated webrev: http://cr.openjdk.java.net/~prappo/8066867/webrev.01/

-Pavel