Rework Endurance enchants

Currently enchanting endurance is pretty pointless for the most part other than preventing easy strip by BBH etc.

Rework it so that => every time your endurance go up in tier of enchantment, add DR+1 to the armor piece.

This means each armor piece can have up to +17DR if anyone ever invests that much into the frags, slightly adding value and stimulating the market place.