preliminary cbk generation
preliminary cbk generation

The Locations.cbk file is used as a checksum for the Locations.itdb file.
This commit adds the calculation of the sha1s it's made of but is missing the
final signature which is added to the 1st 46 bytes of this file.

hyperair/libgpod,neuschaefer/libgpod,neuschaefer/libgpod,hyperair/libgpod,neuschaefer/libgpod,hyperair/libgpod,neuschaefer/libgpod,hyperair/libgpod,hyperair/libgpod,neuschaefer/libgpod