Breaking Changes:

* Split LBA up into 3 different modules:
    * Core contains all of the basic functionality for creating and accessing Attribute instances from other blocks
    * Items contains everything related to item inventories. (Essentially everything in the "alexiil.mc.lib.attributes.items" package).
    * Fluids contains everything related to fluids. (Essentially everything in the "alexiil.mc.lib.attributes.fluids" package).
    * Plus one more (fake?) module: "all", which just nests the other 3 modules.
* FixedItemInvView.isItemValidForSlot no longer accepts an empty itemstack.
* FixedItemInv.getGroupedInv() now mandates that the return value must always be valid so long as the FixedItemInv that returned it is still valid.
* FixedItemInv.getSubInv() and getMappedInv() now allow returning the same object if the sub or mapped inventory has the same slots that the original inventory had.

Changes:

* Updated to Minecraft 1.14.2 and fabric API 0.3.0
* Added LimitedFixedItemInv, which allows exposing a FixedItemInv with more control over the insertion and extraction possibilities.
* Added DelegatingFixedItemInv, which is an abstract base class for implementing a wrapper around FixedItemInv. (Which LimitedFixedItemInv extends)
* Added ItemInvUtil.insertSingle and extractSingle as backed helpers for implementations of various methods that use FixedItemInv.
    * Similar methods were also added to FluidVolumeUtil.
* Made SingleItemSlot implement ItemTransferable (and SingleFluidTank implement FluidTransferable)
* Moved the check for correct overrides of SimpleFixedItemInv.isItemValidForSlot and getFilterForSlot from the implementation of getFilterForSlot to the constructor.
* Added DirectFixedItemInv, as an alternative option instead of SimpleFixedItemInv which allows modifying the stack returned by "getInternalStack". 
    * Unlike items, there is not an alternative for fluids at the moment.
* Added a few shorthand method variants for ItemInsertable.insert and ItemExtractable.extract.
    * All of these have an implied Simulation.ACTION argument appended to the actual invocation.
* Added several methods to the fluid side of LBA that the items module already had:
    * FluidInsertable.getPureInsertable()
    * FluidExtractable.getPureExtractable()

Bug Fixes:

* Made SimpleFixedItemInv.setInvStack allow extracting items that aren't valid for the current filter.
    * In addition it now always allows extracting the entire stack (via setInvStack(ItemStack.EMPTY))
* Fixed the CustomAttributeAdder for all ItemAttributes not correctly respecting SidedInventory.canInsertInvStack() and canExtractInvStack()
