duplicate functions via RASTBuilder

...fle.r.engine/src/com/oracle/truffle/r/engine/REngine.java

.../com/oracle/truffle/r/nodes/builtin/RBuiltinPackages.java

...tin/src/com/oracle/truffle/r/nodes/builtin/base/Args.java

...c/com/oracle/truffle/r/nodes/builtin/base/AsFunction.java

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

...e.r.nodes/src/com/oracle/truffle/r/nodes/RASTBuilder.java

...fle.r.nodes/src/com/oracle/truffle/r/nodes/RRootNode.java

.../com/oracle/truffle/r/nodes/builtin/RBuiltinRootNode.java

...acle/truffle/r/nodes/function/FunctionDefinitionNode.java

...acle/truffle/r/nodes/function/FunctionExpressionNode.java

...acle.truffle.r.parser/src/com/oracle/truffle/r/parser/R.g

.../src/com/oracle/truffle/r/runtime/nodes/RCodeBuilder.java