Rewritten to use VectorAccess.

...acle/truffle/r/nodes/builtin/base/BaseGammaFunctions.java

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

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

.../oracle/truffle/r/nodes/builtin/base/ChooseFunctions.java

.../src/com/oracle/truffle/r/nodes/builtin/InternalNode.java

...est/src/com/oracle/truffle/r/test/ExpectedTestOutput.test

...om/oracle/truffle/r/test/builtins/TestBuiltin_choose.java

...com/oracle/truffle/r/test/builtins/TestBuiltin_lbeta.java

...m/oracle/truffle/r/test/builtins/TestBuiltin_lchoose.java