Support forwarding FTN netmail to user's forward-to netmail address

There's no new opt-in option for this new feature - maybe there should be.
For geneb.
14 jobs for master in 16 minutes and 18 seconds (queued for 12 seconds)
Status Job ID Name Coverage
  Build
passed #2940
FreeBSD
jsdoor-freebsd

00:05:27

passed #2941
Linux
jsdoor-linux

00:05:55

passed #2943
FreeBSD
jsdoor-windows

00:03:42

passed #2935
FreeBSD
sbbs-freebsd

00:06:36

passed #2930
Linux
sbbs-linux

00:07:44

passed #2933
Windows
sbbs-windows

00:06:01

passed #2942
FreeBSD
sexpots-freebsd

00:00:15

passed #2931
Linux
sexpots-linux

00:00:10

passed #2934
Windows
sexpots-windows

00:00:25

passed #2938
FreeBSD
syncdraw-freebsd

00:00:27

passed #2939
Linux
syncdraw-linux

00:00:32

passed #2936
FreeBSD
syncterm-freebsd

00:01:19

passed #2932
Linux
syncterm-linux

00:01:50

passed #2937
FreeBSD
syncterm-windows

00:02:27