experimental? internal functions with M flag

perlexperiment points at perlguts, referencing "internal functions with M flag"

perlguts says:

  M  This function is part of the experimental development API, and may
     change or disappear without notice.

I don't see any reason to call this out specifically as a line item in
perlexperiment.  autodoc suggests that any function flagged M or x gets this
text added:

  NOTE: this function is experimental and may change or be
        removed without notice.

There are by a very rough count, 90 such functions.  I don't think it is useful
to document them all in perlexperiment, either.

(I wonder how useful the x and M flags are in practice?  That's probably a
separate issue.)

Unless someone provides a good objection, I will remove this piece of
perlexperiment.

-- 
rjbs

• experimental? internal functions with M flag by Ricardo Signes