Patch 1 (home-assistant#7926)

* Add octoprint as possible ignore.

* Added octoprint as supported component as well

based on review feedback from ludeeus.

source/_components/discovery.markdown

@@ -30,6 +30,7 @@ Home Assistant can discover and automatically configure [zeroconf](https://en.wi
  * [Logitech Harmony Hub](/components/remote.harmony/)
  * [Logitech media server (Squeezebox)](/components/media_player.squeezebox/)
  * [Netgear routers](/components/device_tracker.netgear/)
+ * [Octoprint](/components/octoprint/)
  * [Panasonic Viera](/components/media_player.panasonic_viera/)
  * [Philips Hue](/components/light.hue/)
  * [Plex media server](/components/media_player.plex/)
@@ -85,6 +86,7 @@ Valid values for ignore are:
  * `ikea_tradfri`: IKEA Trådfri (Tradfri)
  * `logitech_mediaserver`: Logitech media server (Squeezebox)
  * `netgear_router`: Netgear routers
+ * `octoprint`: Octoprint
  * `openhome`: Linn / Openhome
  * `panasonic_viera`: Panasonic Viera
  * `philips_hue`: Philips Hue