HTCONDOR-1374 Document BATCH_SYSTEM environment variable
HTCONDOR-1374 Document BATCH_SYSTEM environment variable

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