Remove dead code.
Eliminate on Q:PIR, mark out rest for Parrot only.

For the Range one, it's an optimization, so can fall back on slow path
until we implement the fast path again on JVM. The rest just throw an
NYI for now.
Dozens of pir:: -> nqp:: in CORE.

Also, mark a few other pir:: out in #?if parrot sections and die NYI
for JVM.