bug fixes and extra functionality for MASS package install/load

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

.../com/oracle/truffle/r/nodes/builtin/base/BasePackage.java

...om/oracle/truffle/r/nodes/builtin/base/FileFunctions.java

...in/src/com/oracle/truffle/r/nodes/builtin/base/Xtfrm.java

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