Balance fixes to medical side-effects.

- Bandage/ointment now causes itch instead of cramps
- Reduced amount of messages/effects by side-effects to 1/3
- Side-effects will now disappear after a while if left untreated, but they will cause damage before that.

code/game/objects/items/stacks/medical.dm

@@ -53,7 +53,7 @@
 				user.visible_message( 	"\blue [user] salves wounds on [M]'s [affecting.display_name].", \
 										"\blue You salve wounds on [M]'s [affecting.display_name]." )
 
-		H.add_side_effect("Cramps")
+		H.add_side_effect("Itch")
 		H.UpdateDamageIcon()
 	else
 		M.heal_organ_damage((src.heal_brute/2), (src.heal_burn/2))