0.2.1906.10 First version of campaign prototype

The default branch now includes a very early version of a "survival sandbox" overworld where you have a persistent fleet in a small universe of warring factions. It only has minimal graphics and UI, but many of the intended core mechanics are there such as Newtonian fleet movement, persistent fleet damage, resource scavenging from battle debris, power struggle between AI factions, and a simple resource economy to generate fleets for you to raid.

Please let me know what you think. It has been quite a while since last update, so I thought releasing this in the current state is better than just continuing the radio silence while making slow progress.