FFI improvements; call parseRd through ToolsRFFI

...ary/src/com/oracle/truffle/r/library/tools/C_ParseRd.java

com.oracle.truffle.r.native/fficall/jni/Makefile

com.oracle.truffle.r.native/fficall/jni/src/externalptr.c

com.oracle.truffle.r.native/fficall/jni/src/listaccess.c

com.oracle.truffle.r.native/fficall/jni/src/misc.c

com.oracle.truffle.r.native/fficall/jni/src/rf_functions.c

com.oracle.truffle.r.native/fficall/jni/src/rfficall.c

com.oracle.truffle.r.native/fficall/jni/src/rffiutils.c

com.oracle.truffle.r.native/fficall/jni/src/rffiutils.h

com.oracle.truffle.r.native/fficall/jni/src/typecoerce.c

com.oracle.truffle.r.native/fficall/jni/src/vectoraccess.c

com.oracle.truffle.r.native/library/tools/src/gramRd.c

com.oracle.truffle.r.native/library/tools/src/tools.h

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

...com/oracle/truffle/r/runtime/ffi/jnr/CallRFFIWithJNI.java

...com/oracle/truffle/r/runtime/ffi/jnr/JNR_RFFIFactory.java

....r.runtime/src/com/oracle/truffle/r/runtime/RContext.java

....r.runtime/src/com/oracle/truffle/r/runtime/ffi/RFFI.java

...oracle/truffle/r/runtime/ffi/RFFIContextStateFactory.java

...ime/src/com/oracle/truffle/r/runtime/ffi/RFFIFactory.java