#5 Small patch for vcard tool

[Hans de Graaff]

The following patch changes the vcard tool to write out
the .vcf files to numbered files. This makes them a bit
harder to find back, but it also ensures that we don't
create filenames with forbidden characters in them. The
patch also contains an encode routine to work around
some of the strange separators in the vCard format.

[Hans de Graaff]