[sane-devel] genesys bakend update

[stef]

	Hello,

	thanks to an hardware donation of Jack McGill, Pierre Willenbrock and me have 
been able to develop and test calibration for gl646/gl84[12] based sheet fed 
scanners supported by the genesys backend.
	These scanners have now a 'calibrate' button option that starts the process 
of calibrating by using the vendor provided calibration sheet. The calibration 
data is stored in a file, so calibration can only be done once. There is also 
another option 'need calibration' which is set when the scanner needs to be 
calibrated.
	 By using these 2 options an frontend can drive the calibration process. But 
I suppose this could be improved when the SANE API will evolve.

Regards,
	Stef