Implement review notes adding_spark

[steersbob]

File: adding_spark.md
Commit: 5be4c2c
Review date: April 12 2021
Tech: Tested on laptop with kubuntu 20.04 LTS. Spark with Fermentation Fridge wizard blocks (standard). Spark is powered & connected over USB.

l26: Curious: I can imagine you can flash the wrong Spark when multiple are connected, but why does this go wrong? How does that work?

l32: brewblox-ctl flash curious the flash sequence gives this warning:

INFO Stopping services...
Removing network brewblox_default
WARNING: Network brewblox_default not found.

The network is removed, and results in a warning. Doh! Maybe suppress the warning and replace with a confirmation message upon success?

l33: brewblox-ctl wifi results in:

INFO This command is temporarily disabled
INFO To set up Wifi, connect to the Spark over USB
INFO On the Spark service page (actions, top right), you can configure Wifi settings

Is the information still correct? Maybe remove the command and / or update the guide. Oh, brewblox-ctl --help mentions the command is disabled. Remove maybe?

l40: commented spark-one service in docker-compose.yml before add-spark command. brewblox-ctl add-spark command results in:

How do you want to call this service? The name must be unique: spark-two
argument of type 'NoneType' is not iterable

removing the service from the file results in the same error. Should have used the brewblox-ctl remove command.
Second try with brewblox-ctl add-spark works. Spark was already set up & configured during previous installation so was discovered twice; over USB and over WiFi.

INFO Discovering devices...
device 1 :: usb 400058000551353432383931 P1
device 2 :: wifi 400058000551353432383931 192.168.1.66 8332
Which device do you want to use? [1]: 1

USB was selected. Both devices have the same Device number 400058000551353432383931, can they be recognized as one device?

l42: scrap, double information.

l44: add: "Adding your Spark to Brewblox with the brewblox-ctl add-spark command results in a generally sesible configured service. If you want to fine-tune..."

l46: -special arguments not tested-

l48: Could --device-host=HOSTNAME work too? We just updated the Getting started section with this option... Prevents ppl from having to fiddle with their router. You do get exposed to strange network errors in userland

l54: cannot test. Spark was already added before and is immediately recognized.

l58: animated gif shows service page starting in list-view. We just changed that to diagram-view.