Upgrade zeroconf to 0.19.0

[fabaff]

0.19.0

• Windows netmask bug was fixed
• Comments and examples updated

Tested with the following configuration:

zeroconf:

Discovery is working as expected.

$ avahi-browse -alr
+ eth0 IPv4 Home                              _home-assistant._tcp local
= eth0 IPv4 Home                              _home-assistant._tcp local
   hostname = [Home._home-assistant._tcp.local]
   address = [192.168.0.70]
   port = [8123]
   txt = ["base_url=http://192.168.0.70:8123" "requires_api_password=true" "version=0.41.0"]

[mention-bot]

@fabaff, thanks for your PR! By analyzing the history of the files in this pull request, we identified @robbiet480, @balloob and @rmkraus to be potential reviewers.