implement CompUnitRepo::Local::File.files()

Now we would be in a position to require .pl scripts by path.
fix signature of CompUnit.new
Add Mu.note
hey, this test already passes 100%
This test is fudged; run it
This test is fudged, run it.
"die" will now say "Died"
Fix %a{5}:delete, as reported by psch
Bring implementation (exists|delete)_key in line
Make "note" say "Noted"
Some ChangeLog additions
Further work on optimizing :delete in sink context
Remove "eval" from poison list

That should never happen anymore, as it's called EVAL now.
RT #122469 coerce indent()'s arg to Int
Update to new QAST annotations API.
Further simplify creation of CompUnit object
unbust term:<∅> for usage as empty set
remove fossil about term:<∅> in the setting
Update to latest MoarVM; use new extop API.

Changes are to make JIT of extops rather easier to implement. This
may also be a small efficiency win, though a shiny C compiler will
probably have done alright on the previous code anyway.
unbust >1600 parrot spectest failures introduces by 9515bb7

This patch does not really fix the issue on parrot, it just fudges
the by the patch changed lines so these will only be made ative for
jvm and moar.
Sidenote: proto prefix:<+^>($?, $?) and proto prefix:<~^>($?, $?)
were changed to take precisely one argument, since these are prefixes.