Makefile template for freebsd port: adjust to newest freebsd version

:T -> :tl
freebsd port: stagedir support
gpsman <-> gpx: srt:device <-> creator

Currently conversion from gpx to gpsman is limited to creator values
matching "etrex", as creator has a different semantics than
srt:device: creator may also be a software component, but srt:device
is always a gps device.

With tests.
data update (very minor)