Add a clojure equivalent of >>>.
The patch implements a new unsigned-bit-shift-right function that has the semantics of Java long >>>. This differs in particular in the handling of the shift distance which uses the least significant 6 bits of the shift distance (thus always in the range 0-63 inclusive). A Java method Numbers.unsignedShiftRightInt is included but not used by the surfaced function.
Screened by: Alex Miller
Related ticket: Ticket
CLJS-514 has been created to track the future work of making ClojureScript's name for this operation the same as the one used in Clojure, after this ticket is completed. David Nolen is agreeable to making this change, even though it would rename an already-defined public function.