[tlbuild] just built custom binaries doesn't contains the 'biber'

[Karl Berry]

I wrote tersely about the situation with biber at
http://tug.org/texlive/build.html#biber.  As stated there, indeed, the
biber sources are not included in the TL source tree, and won't be.

You could perhaps download the biber binary for your system (assuming
it's one of the supported ones) either from sf or from TL and put into
your bin/custom/ directory, if you don't want to build it from the
original source.

I believe that using the bin/custom setup means that tlmgr will never
install updates to any executables, i.e., to add new scripts or update
existing ones.  Or updates to biber.  You should get updates to the rest
of the TeX tree, though.

k