Added script to deprecate the SetDefaultDepotSpecMapField.py, useful
when upgrading from older SDP environments.
This will be deployed in into a new /p4/common/upgrade_sdp directory,
separate from /p4/common/bin, as is a one-time-per-data set script
only done as part of the SDP upgrade process. Actually getting this
deployed will require a tweak to mkdirs.sh, which will be coming