Zeroconf custom component for ESPHome

Example configuration:

zeroconf:
  - service: myservice
    protocol: tcp
    port: 8080

Result:

 _myservice._tcp      local
   hostname = [my_esphome_node.local]
   address = [172.16.0.174]
   port = [8080]
   txt = []

Adding some txt records:

zeroconf:
  - service: myservice
    protocol: tcp
    port: 8080
    txt:
      version: 1.0
      location: basement

Result:

 _myservice._tcp      local
   hostname = [my_esphome_node.local]
   address = [172.16.0.174]
   port = [8080]
   txt = ["version=1.0" "location=basement"]

(Test results obtained with avahi-browse -a -r)