Mark donations as recurring

Hi Rasmus,

I have fixed the indenting a bit to make the code easier to read and I have added a few lines to mark donations from the old website as "recurring", and they can all be related to each other.

Regards,
Ignacio
These are the important lines: if the subscr_id is present and _dgx_donate_repeating is empty, then mark the donation as repeating and use the "subscr_id" as a unique identifier.