[tex-live] src specials fixes

[Olaf Weber]

Sebastian Rahtz writes:

> Fabrice, I think we should follow Olaf's suggestions.
> Can you do that in texlive?

Points to note:

- The message I implemented is 'source specials enabled'.
  We may want to do something different, or capitalize it, or
  whatever.

- In the long run, I think we should be able to properly get away with
  this message here rather than banner changes if we manage to get the
  source-specials to be transparent for a TeX run.

-- 
Olaf Weber

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