Add new API for transferring data from a Readable to an Appendable like already existing InputStream.transferTo(OutputStream).
This CSR covers the enhancement request: JDK-8066870
In order to transfer all data from a Readable to an Appendable mostly the same code has to be written or an external library has to be used instead. This overhead could be reduced by introducing such behaviour directly within the JDK as already available on InputStream for byte data.
Add an new API that implements the behaviour that else needed to be written by the user.
Detailed changes see webrev