Discover slave devices on local network

[ccrisan]

Is your feature request related to a problem? Please describe:

It is often difficult to know the (IP addresses or hostnames of the) qToggle devices on my network. Some of them may not be yet added to my (possibly new) hub. I should be able to quickly scan and adopt all qToggle devices on my network, using a hub.

Describe the solution you'd like:

• Existing device discovery mechanism (which is based on AP clients) should be generalized to allow other types of discovered devices.

• A nmap-based discovery mechanism could use the following command to quickly scan for devices:

   nmap -n -P0 -p 80 192.168.1.0/24 --min-parallelism 64 --host-timeout 2
  

• Using Python-based parallel HTTP requests, one could quickly determine devices that are adoptable.