Wrong bool properties cast to redis

[mix359]

Hi,
I've started playing with this software today, and first of all, thanks for your work!

I'm interested in creating a multicast link to stream the same audio on many buildings of the school I work.
Trying the package I was having a continues "CRITICAL - No data received for 3 seconds!" message so I've red all the code and found that the multicast selection is not set correctly on the receiver.

In particular, in the LinkConfig object the multicast (and all the bool value) is set as a int on redis (line 54), read back as a string and compared with the string 'True', that could never work.
So I've changed the line 54 to
value = ('True' if value else 'False')
and now it work.

Hope this can help.
Let me know if you need the PR with the modification or you can integrate it directly ;)
Cheers Mix