Made several changes in this update, some of which I can't even recall.
Added experience info to the tome lore.
Implemented maximum amounts for the tomes.
Changed to using experience points rather than just levels for storage.
Added Spigot update checker api (only to console on launch)
Works on level-basis unless player has less than a level worth of exp, in which it just stores what they have available (tome space permitting)
Tomes can now be used while in player's off-hand use as well as main hand.
Added custom enchantments (can only be gained by crafting them, spigot API limitations) and combining them in crafting window to allow for 5-tier tomes (same as the original mod does).
Has tiers (can be enabled by permissions):
Default/0 - 10,000
Tier 1/Holding I - 15,000
Tier 2/Holding II - 20,000
Tier 3/Holding III - 25,000
Tier 4/Holding IV - 30,000 (~98 Levels)