Improvement: Boss Refactors

[bconlon1]

Slider

• Configurable: Slider's Labyrinth Boss Music

Valkyrie Queen

• Can be damaged by projectiles, e.g. darts, hammer, etc.
• Immune to knockback from projectiles.
• Potentially buff health slightly.
• Configurable: Boss Music

Sun Spirit

• Shouldnt work in peaceful.
• When hit by Ice Crystals, will still receive damage (probably, but maybe less now?), but will continue to stay in the frozen texture state for a slightly longer amount of time, indicating it can be damaged by the player's weapons as well now (including projectiles) (but has knockback immunity to all attacks). The frozen state could also possibly make the Sun Spirit slightly slower for attack. The Sun Spirit also shouldn't deal as much damage and shouldn't set the player on fire during the frozen state.
• Potentially change minion spawning to be based on health stages instead of on damage.
• Potentially buff health slightly.
• Configurable: Boss Music (fireboss?)