TescoBank always needs to look at at least one historical statement, as
otherwise we lose the transactions that occur at the end of the period.
HSBCMerge now updates balance and stuff.
Add support for CreditCards to HSBCMobile.
Start adding support for CreditCards to HSBC - need to wait a couple of days to see how CREDIT transactions appear on the website before I can finish this one.
Fix TescoBank Balance calculation to be current balance, not the balance from the last statement.
Transactions view page now understands the "period" param.

When redirected to taggedtransactions from the data view, the period will now be passed along also.
When a period is passed to transactions, it will hide accounts with no transactions in the given period.

Date display when tagging transactions is now done by PHP not javascript to ensure consistency.
Abstract periods a bit to make adding new ones easier in future.