Add MMD candidates for simple Callables

for grep, grep-index, first, first-index, last-index
Merge branch 'nom' of https://github.com/rakudo/rakudo into eleven
Properly MMD grep/first and friends
Fix Supply.grep for Regexes
Mention optimizations in grep/first and friends
bump nqp/moar rev for bigint fixes
assign to PROCESS.WHO instead of bind, so we can "temp" things
allow to switch to Perl 5 module by switching to a foreign statementlist

This makes "use v5" work, though this is not the ideal patch for slangs
implemented in Perl 6 itself. We only do it this way for now to have
something at all. jnthn++ for reviewing
Properly implement $*PERL according to spec

This introduces the Perl and Compiler classes
Mention $*PERL upgrade
fix my scoped regexes in classes

Regexes tried to install itself into the class, and then exploded by getting a Cursor instead
of the type of the class.
Fix advent test fail caused by grep optimization

MMD candidates for grep and friends where selected on Callable and Regex,
instead of the more correct Callable:D and Regex:D.  This caused grep
expecting to smartmatch on Callable type to fail.
Mention "use v5" no longer being noop
bump nqp/moar rev for num->str fix
Replace bitshift `+>` with `div` operator

Reads better (imho). Works around RT#121909 which is currently resulting in significant failures in S03-temporal on parrot.
Merge pull request #270 from dwarring/patch-1

Replace bitshift `+>` with `div` operator in ymd-from-daycount
Add .fmt to (Set|Bag|Mix)(|Hash)
Fixes to Compiler class, found while making tests
bump nqp/moar rev for to unbreak test that fail under spesh
add myself for release on May 22