Usage: storage.importTransaction(transaction, metadata?)
Description: Allow to import a transaction to the store.
Notes: TransactionObject needs to contains basic vin/vout information.

Parameters:

parameters	type	required	Description
transaction	Object/Transaction	yes	The transaction to import to the store
metadata	TransactionMetaData	no	The transaction metadata

Returns: Boolean
Emits: FETCHED_CONFIRMED_TRANSACTION/FETCHED_UNCONFIRMED_TRANSACTION