Added some EMC items.
Merge branch 'master' of https://github.com/mangstadt/emc-shopkeeper.git
Fixed a bug where bonus/fee transactions were counted multiple times.

The updater failed to consider the date of the most recently parsed
bonus/fee transaction when running an update.  This caused bonus/fee
transactions to be counted more than once if an update operation only
parsed bonus/fee transactions.  Continually clicking "update" would
repeatedly parse the same bonus/fee transactions and repeatedly
increment the bonus/fee totals in the database.