Added check for upper case card details

If the card is not found in the initial check, we now check again with
the card in upper case to ensure that it is definitely not in the
approved user list. Not elegant, but should work.
Merge pull request #3 from EdBrereton/master

Added check for upper case card details.

Will do for now, but better in future to format the existing data as all lowercase, and then read each card as all lowercase. Probably want to do part of that in the export code of the member area though