Add definition for Sensirion SGP30

[tyeth]

@brentru @lorennorman
There's a minor hiccup:
The schema for the i2c component subtypes doesn't have TVOC, but it is included in the Adafruit_Sensor repo, so I assume that's the correct value to use, along with eco2 for the SGP30. The i2c component schema will need updating to add the tvoc type

[lorennorman]

@tyeth perfect, thanks for this work and the note.

I've just added a commit with the tvoc sensorType added, that validation step should pass now. I'm going to go look in our other repos and see if there's other places i need to account for it.

@brentru I was looking at this list to see what all sensor types are in there:
https://github.com/adafruit/Adafruit_Sensor#standardised-si-values-for-sensors_event_t

We don't seem to be one-for-one with that list, is that expected? Or should we try to match that closely?

[lorennorman]

Other places to update:

• web frontend (done, linked to this PR)
• mqtt broker (done, linked to this PR)
• protocol buffers (@brentru)
• ws arduino (@tyeth or @brentru)

[tyeth]

Seen the file size image issue, woops forgot that bit, only remembered a limit for GIFs.
Will carry on in the morning

[tyeth]

@lorennorman I no longer have the ability to rerun due to your commit touching restricted files, but should be fine.

[brentru]

@lorennorman @tyeth Enumerated type for TVOC has been added within WipperSnapper_Protobuf and wrappers have been compiled and merged into WipperSnapper_Arduino.

[brentru]

@tyeth You should be un-blocked and able to continue. Please leave @lorennorman and I any notes in here if you are still encountering issues with the broker/types

[ladyada]

lgtm