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
Merge remote branch 'upstream/nom' into date-patch
use arithmetic div instead of +> bitshift in date calculations.