BeaconThings: Support for multiple mobile devices / accounts #2

When registering the iBeacons with SmartThings through BeaconThings, the beacons are always registered as BeaconThings-<MAJOR>-<MINOR>.

    def beaconId = "BeaconThings"
    if (beacon.major) {
      beaconId = "$beaconId-${beacon.major}"
      if (beacon.minor) {
        beaconId = "$beaconId-${beacon.minor}"
      }

https://github.com/obycode/smartthings-smartapps/blob/master/BeaconThings/BeaconThingsManager.groovy#L70-L75

The native BeaconThings iOS application allows multiple devices to pick up iBeacons; however, due to the registration limitation described above, the having multiple devices causes duplicate registrations in SmartThings and/or devices with the same device network id (e.g. BeaconThings-1-1), even with multiple accounts.

Suggestion: Include more information within the device network id to better identify multiple devices and/or accounts.

For example: if each device had its own SmartThings account, the account plus the Major/Minor could be used to identify the specific account (e.g. user@domain.com|BeaconThings-1-1). This could be further improved by further identifying a specific device, similar to the mobile device presence device in SmartThings itself. This would allow devices to be distinguished for rules (e.g. iPhone, iPad, etc.) and accounts.