[freeciv-data] RFC future techs/units/improvements

One thing I liked about playing CTP was all the future techs and
associated improvements and units.

While Freeciv has a few techs that might be considered "future" as well
as a future wonder, I think it would be cool to include some more.

I know that many multiplayer games never make it much past steam engine,
but lots of people (in fact most of them) play singleplayer.

So this is a request for comments on adding future stuff :)

Please respond with ideas of future techs, units, improvements and
wonders that could be included into Freeciv's rulsets.

-- 
Paul Zastoupil