Add Ultra Heart Fly

[ryondinkus]

Resolves #49

Adds a new Heart Fly type called the Ultra Heart Fly. Item grants one of him one pickup and one on each new floor.

He has many abilities of the basic flies, including: Orbital:

• 2x contact damage
• Can absorb two bullets instead of one
• Can poison or midas freeze enemies on collision
• Does Necronomicon effect when absorbing bullet
• Spawns two blue attack flies on room clear
• Counts as a Red Fly and a Soul Fly for Devil Deal purposes (IN PROGRESS)

Attack:

• 2x contact damage
• On enemy collision, chance to either fear, midas freeze, or poison enemy
• Fire 8 bone tears in all directions on enemy collision
• Spawn 1-8 pennies on enemy collision