Bug 6273: add support for recording type of payment made via SIP2

Adds support for recording in Koha accountlines a different accounttype
depending on how the fee was paid at the SIP2 station (cash, credit,
etc.)

Adds a new param to recordpayment(), $sip_paytype, which is appended to
the 'Pay' type if present.  The payment description is also appended
with " (via SIP2)" if this is present.

In order for other scripts to keep working as expected, "eq 'Pay'"
needed to be replaced with a regex comparison "=~ /^Pay/", so that 'Pay'
and 'Pay-##' would continue to group together.

To test:
1.  Make a payment over a SIP2 connection
2.  Check the patron record in the staff client; you should see the
    modified description
3.  Attempt to print a invoice or a reciept for the borrower; the
    payment should show up where expected

Signed-off-by: Benjamin Rokseth <benjamin.rokseth@kul.oslo.kommune.no>
Signed-off-by: Brendan Gallagher <brendan@bywatersolutions.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Bug 6273: (follow-up) fix various issues

This patch fixes various issues that prevented the account
type from being set correctly when recording SIP2 payments:

- the fixed fields in the fee paid message were not getting
  parsed correclty
- accountlines.accounttype is only five characters wide, so
  SIP2 payments are now records as 'Pay00', 'Pay02', etc. rather
  than 'Pay-00'.
- removed regression on bug 2546 and made the new payment types
  translatable

Signed-off-by: Galen Charlton <gmc@esilibrary.com>