Update to Freeciv server r34494.
Update to Freeciv server r34494.

Freeciv commit message:
Added support for extras that can hide units inside from opponents.

Requested by Jacob Nevins <jtn>

See patch #4101

andreasrosdal/freeciv-web,andreasrosdal/freeciv-web,adaxi/freeciv-web,adaxi/freeciv-web,adaxi/freeciv-web,andreasrosdal/freeciv-web,andreasrosdal/freeciv-web,andreasrosdal/freeciv-web,adaxi/freeciv-web,adaxi/freeciv-web