mts code reorganization

[Shantonu Sen]

As I mentioned in my last email, I've moved over code from
zotnet/mts to mts/generic, and made a more comprehensive
archive called libmts.a which includes the contents of mts/generic
and mts/smtp (which was previously in libsmtp.a). The details
are in the ChangeLog. I don't anticipate any problems, since I
didn't actually change any code.

This makes the zotnet/ directory unnecessary, which cluttered
the top-level directory anyway.

Shantonu