[arch-dev-public] [signoff] licenses-2.6-1

Fixes FS#18857, Missing FDL1.2/license.txt file. Also a general cleanup of the PKGBUILD using that handy makepkg feature that can rename downloaded files so things like "3_0.txt" aren't sitting around. If FDL 1.2 is there and some other random license of your choosing is working too, that should be good for a signoff. -Dan