Apply TADL-specific SIP patron barcode transforms
TADL has some SIP clients which are not capable of removing extra characters
from some scanned patron barcodes. Thus, we handle that on the SIP server side.
If no active card is found with the barcode provided in the SIP request, first
see if it starts with an uppercase letter. If so, lowercase it, then determine
if certain length requirements are met, and if so also truncate the value.
Attempt to find an active card via the resulting value, and return the usual
error if not found.
Signed-off-by: Jeff Godin <jgodin@tadl.org>