Save config when starting (so that new properties get written into it)
Add option to spawn boss by replacing with other mob
Remove stack trace printing
Resave root-only config props too
Move boss properties into a single class
Check if boss already exists before recreating him
Replace boss by array of bosses
Add multiple bosses to config
Fix problem with not finding boss id
Save hp for multiple bosses
Change property altering functions to account for multiple bosses
Add commands to create and remove bosses
Change displayed message for add and remove boss commands
Reset counterattack timer when a boss dies