SHM Control, physical siren trigger, bugfix

[thebillness]

Added the ability to control SHM via virtual switches. The switches are defined on the Preference page of the SmartApp.

Added the ability to define a speed key (ABCD) to be executed as a SHM siren. The Speed Key is selected in the Partition Device's settings. Honeywell typically defaults the B key to Police Panic. If the B key is selected in the settings, when the SHM siren event fires, the Honeywell siren will sound.

Multi activation bugfix: It was late and my brain wasn't working so I inadvertently triggered the virtual switch changes with any zone change. This has been resolved.