Minor patches to initial tower view code. Added calculation for "tower" at
any airport, placed a couple fractions of a degree off the center. Moved the
farplane from 100m to 5km so that "lookfrom" mode can see the model. 5km is
still in a reasonable range for a depth buffer. Note that looking at a model
anything but a small distance will cause some problems on older cards.
Temporarily changed viewer to always report elevation/lon/lat of the aircraft
in order to avoid a problem with the ground trim getting recalculated when
tower and aircraft are on different tiles.