Ability to parse alerts without "Occupants of"

[blakecooper]

The phrase "Occupants of" was previously considered an invariant, and was therefore used to orient the parser in the file. For this reason, alerts are considered malformed (i.e., the script exits) when this phrase is not present in the Facilities notice. However, there are rare alerts that don't use this phrase, and the script should be able to parse these as well.