License change in LibRaw due to inclusion of demosaic packs

[Siddhesh Poyarekar]

Hi,

I got a request to include demosaic packs into the LibRaw build to
support some digital cameras:

https://bugzilla.redhat.com/show_bug.cgi?id=760638

With this inclusion, the LibRaw package will have a GPLv3+ license
since the demosaic packs are released under GPLv2+ and
GPLv3+. Currently only shotwell seems to be using LibRaw and it should
be ok with this change since it is GPLv2+.

Thanks,
Siddhesh