Fix RNGkind + make RRNG class bit lighther

.../com/oracle/truffle/r/runtime/ffi/jni/CallRFFIHelper.java

...le.r.runtime/src/com/oracle/truffle/r/runtime/RError.java

.../src/com/oracle/truffle/r/runtime/rng/RNGInitAdapter.java

....r.runtime/src/com/oracle/truffle/r/runtime/rng/RRNG.java

...m/oracle/truffle/r/runtime/rng/RandomNumberGenerator.java

.../oracle/truffle/r/runtime/rng/mm/MarsagliaMulticarry.java

.../com/oracle/truffle/r/runtime/rng/mt/MersenneTwister.java

...est/src/com/oracle/truffle/r/test/ExpectedTestOutput.test

...le.r.test/src/com/oracle/truffle/r/test/rng/TestRRNG.java

mx.fastr/copyrights/overrides

mx.fastr/mx_fastr.py