imports, static, and various other cleanups

...com/oracle/truffle/r/engine/interop/ffi/TruffleStats.java

...om/oracle/truffle/r/library/stats/RandFunctionsNodes.java

...rc/com/oracle/truffle/r/nodes/builtin/base/Utf8ToInt.java

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

...m/oracle/truffle/r/nodes/function/ClassHierarchyNode.java

...rc/com/oracle/truffle/r/runtime/nmath/GammaFunctions.java

...me/src/com/oracle/truffle/r/runtime/nmath/RMathError.java

...src/com/oracle/truffle/r/runtime/nmath/distr/DNBinom.java

.../src/com/oracle/truffle/r/runtime/nmath/distr/PNBeta.java

...ime/src/com/oracle/truffle/r/runtime/nmath/distr/Pnf.java

...src/com/oracle/truffle/r/runtime/nmath/distr/QNChisq.java

.../src/com/oracle/truffle/r/runtime/nmath/distr/Wilcox.java