Add a feeble version of the old as_string() method for DBI.
Add a feeble version of the old as_string() method for DBI.

For now, map it to dump_results() which has butt-ugly output but is way
better than a "Can't locate object method" exception. Ultimately the few
uses of this method will get replaced by script specific printfs. I see
no reason for a general emulation of this method.

nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome