allow all atomic vectors to store their data in native memory

...ngine/src/com/oracle/truffle/r/engine/interop/ListMR.java

...ruffle/r/engine/interop/RAbstractVectorAccessFactory.java

...c/com/oracle/truffle/r/engine/interop/REnvironmentMR.java

.../src/com/oracle/truffle/r/engine/interop/RFunctionMR.java

.../src/com/oracle/truffle/r/engine/interop/RLanguageMR.java

...e/src/com/oracle/truffle/r/engine/interop/RPromiseMR.java

...ne/src/com/oracle/truffle/r/engine/interop/RSymbolMR.java

...oracle/truffle/r/ffi/impl/common/JavaUpCallsRFFIImpl.java

...m/oracle/truffle/r/ffi/impl/interop/CharSXPWrapperMR.java

...fle/r/ffi/impl/interop/FFI_RForeignAccessFactoryImpl.java

.../truffle/r/ffi/impl/llvm/TruffleLLVM_UpCallsRFFIImpl.java

...le/truffle/r/ffi/impl/nfi/TruffleNFI_UpCallsRFFIImpl.java

...l/src/com/oracle/truffle/r/ffi/impl/nodes/AsCharNode.java

...pl/src/com/oracle/truffle/r/ffi/impl/nodes/MiscNodes.java

.../com/oracle/truffle/r/ffi/impl/upcalls/FFIUnwrapNode.java

...com/oracle/truffle/r/ffi/impl/upcalls/StdUpCallsRFFI.java

...ve/fficall/src/truffle_common/Rinternals_truffle_common.h

...cle.truffle.r.native/fficall/src/truffle_nfi/Rinternals.c

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

...src/com/oracle/truffle/r/runtime/data/CharSXPWrapper.java