Docs for ClassAd substr() crash fix. HTCONDOR-823
Docs for ClassAd substr() crash fix. HTCONDOR-823

htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor,htcondor/htcondor