Improved the checking of "*1284DeviceID:" and "*Product:" lines in the PPD files whether they are really for different models

- if a device ID has no MDL/MODEL field, it is not taken into account as an
  extra model
- If in a device ID a DRV: field is found (Foomatic info) this is added to the
  device IDs of all model entries.
- Model names get normalized before comparing: all lowercase, leading and
  trailing white space stripped, manufacturer name in the beginning removed,
  then only really different models get an extra entry.
- If a PPD contains one or more "*1284DeviceID:" lines and only one "*Product:"
  line, the model name of the "*Product:" line is ignored.

This removes tons of bogus lines, especially in the PPD from Foomatic )both
generated from XML and ready-made PPDs from printer manufacturers) and HPLIP.1

Signed-off-by: Vitor Baptista <vitor@vitorbaptista.com>
Changing version to 1.0.1