RFC: moving to GPL v3 and FDL 1.3

Hi all,

It has been suggested that we move from GPL v2 to v3, and as Stow is
part of the official GNU Project, it seems to make sense to me to "tow
the party line", so I think the next release I make will do this,
unless there are any strenuous objections?

Similarly it would be good if the next release of the manual was under
FDL 1.3, although I will need to contact copyright holders
individually for permission to do that.

Thanks,
Adam