Treat CharSXP as byte array w.r.t. e.g. length

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

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

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

...c/com/oracle/truffle/r/runtime/data/NativeDataAccess.java

...fle.r.test.native/packages/testrffi/testrffi/R/testrffi.R

...uffle.r.test.native/packages/testrffi/testrffi/src/init.c

...e.r.test.native/packages/testrffi/testrffi/src/testrffi.c

...e.r.test.native/packages/testrffi/testrffi/src/testrffi.h

...est.native/packages/testrffi/testrffi/tests/simpleTests.R