Eliminate ‘Can't use \1 to mean $1’ false positives

We need to check that the quote-like operator we are parsing is a sub-
stitution (not just any quote-like operator) and that we are parsing
the right-hand side.
[perl #119807] Deparse s//\(3)/e in a way that does not warn

Code that does not warn should not be deparsed in a way that warns.
s//\3/e produces a warning about misuse of \3 where $3 is meant.
s//\(3)/e compiles to the same thing and produces no such warning.
So B::Deparse should parenthesize references to numbers in the rhs
of a substitution.
Increase $B::Deparse::VERSION to 1.24
pad.h: Correct PadlistMAX docs

They have been wrong since I added them.