Add "sort by vname" for Mike (currently called only from showexp.php).
Add "sort by vname" for Mike (currently called only from showexp.php).

Sort by vname is now the default sort, and you can sort by node_id (the
old sort), and by vname, by clicking on the column title, as usual.

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