Added license expiration check.
Added new 'warning' indicator, so some things may be reported as warnings
rather than errors.
Fixed bug in not-released dev version handling su/exec when started
Enhanced verify_sdp.sh to support being called by other scripts by
giving a reliable exit code. Errors detected result in a non-zero
exit code; warnings do not. This is in support of SDP-444, but does
not complete that job.