* new thumbnail

AI:
* Economic AI was a bit rewritten, so it should be able to cope with new resources for army hiring

Style:
* new icons for lithoid armies

Unified prices and upkeeps:
* prices vary from 15 to 100 of any resource
* upkeeps vary from 0.1 to 1
* robot armies now consume alloys as upkeep (not much)
* lithoid armies consume minerals