+removed mod dependance

+ added preview when building
+ more passway fixing

+ added again passways whre needed (era c2/c3)
+ changed era c entrances availability from 1990 to 1980

+ removed outer passways

+ added more bigger buildings
+ added signs and clocks
+ some fixes

+ removed screenshots from download

+ added menu icons
+ fixed optics

+ added bigger era c building
+ added centered station signs

release