Revert SA certificate signing code for now, since it breaks ION.
Revert SA certificate signing code for now, since it breaks ION.

This reverts commit 102a123e4d34974761747f50df7d502daa4c78c9.

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