Filtering/Caching specific Ring devices
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# Feature Request

### Description
<!-- ✍️--> I have a Ring account which manages upwards of 30 locations at any given time. These locations include both cameras and Alarms. Im only interested in managing the Alarms through Homebridge in order to automate arm/disarm scenes. is there a way to select location ID's and ONLY the specifically Alarm panels? Currently I load all locations (which immediately errors on max # of devices), grab the location ID's and then load only one location at a time and then hide all devices before re-adding other Loacions. I would think not caching unwanted/hidden devices would save resources. Theres probably some config Im not reading somewhere.

## Describe the solution you'd like
<!-- ✍️--> selective managed devices 

### Describe alternatives you've considered
<!-- ✍️--> Have you considered any alternative solutions or workarounds?

### Device data
<!-- ✍️-->  If you are requesting a new device be added to homebridge-ring, please follow the instructions in https://github.com/dgreif/ring/wiki/Data-Discovery and include the output here
