Add interchange 4.8.6, RedHat's database-enabled e-commerce server.
The committed port is an improved and updated version of the submitted one,
thanks to Stefan (Racke) Hornburg <email@example.com> for his helpful hints
about some configure/build internals of interchange.
I decided to take over maintainership of this port for a while until someone
more responsive than the port submitter (no answer so far from him since I
decided to take over the PR) is interested in it or until I think the testing
period of this port is over.
Submitted by: Seth Kingsley <firstname.lastname@example.org>
Thanks to: Stefan (Racke) Hornburg <email@example.com>