lots of scene work

-finished designs for scenes 1, 2, 3, 4, 11
-implemented critical hit chance for bow
-affected by agility stat
-arrows, ghost blade now uses both agility and strength to calculate
damage (agility gives larger damage boost)
-health now affected by strength stat (each stat gives 19 hp)
-mana/energy now affected by intelligence stat (each stat gives 13 mp)
-intelligence AND strength stats now affect mana regen rate
-arrows and ghost blades now require mana to shoot
-implemented (placeholder) mana bar