Containment levels introduced

Multiple changes introduced after receiving feedback from lovely people on discord and reddit. 

• Containment Levels introduced – This is Strife of Stars response to difficulty levels to address the issue of perma-death being very punishable for new players while reasonable for seasoned turn-based pros. 
• Enemy formation overhaul – Changed how enemy formations are structured to introduce more variance in initial positioning
• Multiple bug fixes – Fixed multiple AI, UX and visuals-issues

Level selection:

Ships go boom.