rJava rewrite - fastr changes:

- removed jri
- removed all native code and replced with fastr interop based impl in R
- some tweaks in original rjava R code
- java build part of install

com.oracle.truffle.r.pkgs/rJava/jri/REngine/Rserve/package-info.java

-/**
- * REngine-based interface to <a href="http://www.rforge.net/Rserve/">Rserve</a>
- */
-package org.rosuda.REngine.Rserve ;