santactl: nil prefix value check - fixes #361 (#362)
santactl: nil prefix value check - fixes #361 (#362)

* santactl: nil prefix value check - fixes #361

* santactl: check all filters

google/santa,tburgin/santa,tburgin/santa,russellhancox/santa,tburgin/santa,google/santa,google/santa,russellhancox/santa,russellhancox/santa