remove initial vector access implementation

.../com/oracle/truffle/r/ffi/impl/nodes/ListAccessNodes.java

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

...nodes/src/com/oracle/truffle/r/nodes/primitive/Utils.java

...racle/truffle/r/runtime/data/nodes/EnableNACheckNode.java

...rc/com/oracle/truffle/r/runtime/data/nodes/GetDataAt.java

.../com/oracle/truffle/r/runtime/data/nodes/GetDataCopy.java

...com/oracle/truffle/r/runtime/data/nodes/GetDataStore.java

...com/oracle/truffle/r/runtime/data/nodes/ReadAccessor.java

...rc/com/oracle/truffle/r/runtime/data/nodes/SetDataAt.java

...cle/truffle/r/runtime/data/nodes/VectorAccessAdapter.java

...m/oracle/truffle/r/runtime/data/nodes/VectorIterator.java

...oracle/truffle/r/runtime/data/nodes/VectorReadAccess.java

...racle/truffle/r/runtime/data/nodes/VectorWriteAccess.java