[patch] mbuf aware libalias

[Paolo Pisati]

http://people.freebsd.org/~piso/libalias_mbuf.diff

this patch makes libalias able to handle mbuf: TOS, big MTU, much
less copy-around, etcetc.

I encourage people to test it, since i would like to commit it soon.

Known issues:

-documentation was not updated
-i didn't convert the fragment handling part (GetFragment, SaveFragment&C)
 since i would like to axe it
-all the modules still require some copy-around to work, but i'm  teaching
 them, piece by piece, how to use mbuf

bye,
P.