V5: passenger_monitor cannot terminate orphan workers in a multi-application environment

[radamanthus]

passenger_monitor calls passenger-status to look for orphaned passenger workers:
https://github.com/engineyard/ey-cookbooks-stable-v5/blob/next-release/cookbooks/passenger5/files/default/passenger_monitor#L103

In a multiple-application environment there will be multiple passenger-standalone processes running. Calling passenger-status without a name parameter will result in an error like this, written to /var/log/syslog:

Apr  4 08:44:02 localhost passenger_monitor: It appears that multiple Phusion Passenger instances are running. Please select a specific one by running:    passenger-status <NAME>  The following Phusion Passenger instances are running:  Name                       PID      Description -------------------------------------------------------------------------- pgnOYJGM                   7081     nginx/1.12.1 Phusion_Passenger/5.1.8 keSiecR1                   16255    nginx/1.12.1 Phusion_Passenger/5.1.8
Apr  4 08:44:02 localhost passenger_monitor: Could not read passenger-status [Status:1]
Apr  4 08:44:02 localhost passenger_monitor: It appears that multiple Phusion Passenger instances are running. Please select a specific one by running:    passenger-status <NAME>  The following Phusion Passenger instances are running:  Name                       PID      Description -------------------------------------------------------------------------- pgnOYJGM                   7081     nginx/1.12.1 Phusion_Passenger/5.1.8 keSiecR1                   16255    nginx/1.12.1 Phusion_Passenger/5.1.8
Apr  4 08:44:15 localhost passenger_monitor: Could not read passenger-status [Status:1]
Apr  4 08:44:15 localhost passenger_monitor: It appears that multiple Phusion Passenger instances are running. Please select a specific one by running:    passenger-status <NAME>  The following Phusion Passenger instances are running:  Name                       PID      Description -------------------------------------------------------------------------- pgnOYJGM                   7081     nginx/1.12.1 Phusion_Passenger/5.1.8 keSiecR1                   16255    nginx/1.12.1 Phusion_Passenger/5.1.8