DE2587 Store Allocation Data in Order items

Make reservation id globally unique.
Store allocation data in sales/order_item in order
for order create to access reservation id on the order item.

Conflicts:

	src/app/code/community/EbayEnterprise/Eb2cInventory/Helper/Data.php
	src/app/code/community/EbayEnterprise/Eb2cInventory/Model/Allocation.php
	src/app/code/community/EbayEnterprise/Eb2cInventory/Model/Observer.php