[v0.6.0] Farming and player's HP

 -Player's HP (You respawn to the initial position when it reaches 0)
 -Wheat (it grows when sprinkled on the ground and becomes bread when baked)
 -Slime now eats plants smaller than itself and grows
 -Slimes of various sizes now spawn
 -Probably fixed a bug that Bond / Separate button is pressed twice
 -Other minor fixes