Cleanup After Boss Death
- All minions, bullets, mortars, spawn points, etc. are cleaned up and destroyed after the boss is killed.
- Various tweak for visual appeal and balance.
Unified Phase Settings
- The phase settings for the spawner and mortars have been moved up into the spider tank. No different states only have to choose whether or not to use the spawner and mortars.
Boss Health Display Fix
- Cleaned up the boss's health display so the darker background shows up and it displays correctly for different resolutions.
Merge branch 'master' into final_work

Conflicts:
	Assets/Prefabs/Bosses/Spider Tank.prefab
Merge pull request #181 from ModSquadWorkshop/final_work

Final work