Menu-spec update (Was: [Patch] Update 'How to' to clarify computation of datadir)

[Jeremy White]

> first XDG_*_DIR that's writeable seems reasonable to me, sofar I haven't 
> seen anyone saying it would be unreasonable.

This thread started with a patch by me to make the spec be just that;
Waldo instead committed a change that forced the write directory to
be hard coded to one of either /usr/share or /usr/local/share.

Waldo, a quick note on that - as I read the spec further,
since /usr/local is given in the spec as being ahead of
/usr, and given what we've heard about the FHS,
I think /usr/local should be first in your list.

Cheers,

Jeremy