remove WeakValueHashMap

replace with Guave MapMaker
weak collections improvements
move some collections out of wrappers package
replace literal format character with constant
fix floating items duplicate after server restart

suspect unloaded chunks entity data is flushed/cleared before it can be used to remove the entity.

solution:
if a floating item is despawned while GenericsLib is disabled, it is removed like normal except the entity unique id is not wiped from the data node and a dispose flag is set. The entity is removed the next time the manager loads the data node.
consolidate AbstractFloatingItemManager, FloatingItemManager

add IFloatingItem
organize packages

refactored com.jcwhatever.bukkit.generic --> com.jcwhatever.generic