Merge from vendor branch TNF:

Merge from vendor branch TNF:
Import tex-verbdef-0.2 as print/tex-verbdef.

The package defines a single command \verbdef (which has a *- form,
like \verb).  \verbdef will define a robust command whose body expands
to verbatim text.  By using commands defined by \verbdef, one can put
verbatim text into the arguments of commands; since the defined
command is robust, it doesn't matter if the argument is moving.  (Full
details of syntax and caveats about use are in comments in the file
itself.)