Configurable rsync options for --transfer

[Jay Hacker]

Currently, when running jobs on remote machines, --transfer uses rsync
-rlDzR to send files.  Among other things, this transfers symlinks as
symlinks instead of following them (the "-l").  I would like to copy
symlinks as real files (which I think is rsync -L).  It strikes me
that other people might want different rsync options, so perhaps a
general mechanism is best. We could have an --rsync-opts flag, that
just sets the rsync options; or we could have a --transfer-prog that
lets you specify a different program entirely (like scp).  Thoughts?