put exit status back on every Info page

[Dan Jacobson]

Yes it may be efficient to write one

   Exit status

   ...  For the vast majority of commands, an exit status of zero
   indicates success, and a value of `1' indicates failure.  However,
   some of the programs documented here do produce other exit status
   values and a few associate different meanings with the values `0'
   and `1'.  Here are some of the exceptions: `expr', `false',
   `nohup', `printenv', `sort', `test', `true', `tty'.

Info page, but looking at

   `comm': Compare two sorted files line by line

      Unlike some other comparison utilities, `comm' has an exit status
   that does not depend on the result of the comparison.  Upon normal
   completion `comm' produces an exit code of zero.  If there is an error
   it exits with nonzero status.

even though that just reconfirms the first paragraph, but still with
all these exceptions to exceptions being mentioned, one longs for the
good old days of the Unix manual, where each command's documentation
had an explicit statement about its exit statuses, before you GNU
fellas confiscated them from the man pages and on the Info pages
herded them into that one Info page with that generalization.