Terraforming installation under base tile

[PavelCibulka]

There is an inconsistency between:

• When base is built on top of Condenser, Echelon Mirror (probably more Sensor Array?) they still work.
• These installations cannot be built on a tile after the base is there.
• If terraformer is in process of building them and base is built, it stops terraforming action on the base tile.

I think it should either remove Condenser, Echelon Mirror etc. from the tile when the base is built, or allow building them on a base tile. The situation right now is just a weirder exploit / micromanagement state.

[induktio]

This is maybe related to #109 in the sense it could make sense to adjust some obscure original game rules. Haven't made any decision yet about altering these rules so the issues could wait for later if we get any additional comments.