Add Support for SmartPower Plug
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**Is your feature request related to a problem? Please describe:**
I am frustrated with all the other smart plugs on the market, especially those that have to go through some cloud service. It would be great if this plugin added support for the UniFi SmartPower Plug so that it can be used with HomeKit and Siri.

**Describe the solution you'd like:**
I would like the SmartPower Plug to be supported so that it can be used with HomeKit and Siri.

**Describe alternatives you've considered:**
I've used a lot of the smart plugs on the market. They all suck for one reason or another. 

**Additional context:**
UniFi SmartPower Plug: https://store.ui.com/collections/unifi-accessories/products/unifi-smart-power

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