Add SsdpBridgeLocator

[Indigo744]

As discussed in #198

I took the original SsdpBridgeLocator class and modernized it a bit:

• Regular expression to get substrings
• ConcurrentDictionary for thread-safe working with the list
• don't filter uPnP device at the end, check as soon as a response is received in a new thread
• Get IP from socket and not from response body

It works quite well with my Hue Bridge v2.

I also took the liberty to update HttpBridgeLocator class to use using statement so disposable resource are automatically freed.

[michielpost]

Thanks, works great!

[michielpost]

It's in version 3.13.0 on NuGet https://www.nuget.org/packages/Q42.HueApi/