[m-rev.] for review: stop supporting --tags none

[Zoltan Somogyi]

The reason for this diff is that (a) we have not used this capability
in decades, and (b) continuing to support it would complicate
the code I am working on for putting type representation info
into .int files. So basically the same reason as for deleting
the hl grade component a couple of weeks ago.

For review by anyone.

Zoltan.
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