Set eLv for most items.

 Most equipable items now require a level to be equipped.
 The level sits at the level required for the quest releasing the item,
 when possible. For other cases, a reasonable value is adopted,
 approximating when the player should acquire the item, based on
 previous items he should have at his level.

 Some item stats were adjusted when necessary (e.g too high def despite
 the item deserves to be equipped at low level)

 * Bardiche (despite unused) Atk / Def were swapped.
 * Top Hat: Def 10 -> 5
 * Funky Hat: Def 13 -> 7
 * Mush Hat: Def 10 -> 6
 * Shroom Hat: Def 13 -> 9
 * Chrismas Elf Hat: Def 13 -> 7
 * Face Mask: Def 10 -> 5
 * Eggshell Hat: Def 12 -> 8
 * Colored Eggshell Hats: Def 9 -> 7