Driver for the sensirion sht85 sensor

[konstantinmauer]

Adds a driver for the sensirion sht85 sensor and a sensirion sensor bridge. It uses official drivers of sensirion to communicate with the sensor bridge.

[odnarod]

this thing is getting quite complicated for a temperature sensor 🙈
would like to hear what @DavidLP thinks about some of my comments..

[DavidLP]

Pretty nice first commit into basil!

[DavidLP]

I do not know the Sensirion box etc. so it is tough for me to judge this. From what I read, it works as the following:

• there is a sensirion box that allows to have up to 2 ic2 devices connected to it. This is the TL SensirionSensorBridge
• the i2 devices can be connected to it. A generic i2c device is SensirionBridgeI2CDevice
• a specific i2c device are the temperature devices sensirionSHT85

I mean that is (as I can quickly judge) a very clean and generic implementation to support hardware we have and to support hardware we don't have ;-)

If we are only going to use the bridge with the temperature sensors, one could maybe just make one driver and skip the extra TL.
For lab devices I originally used the TL to specify the means of communication (RS232, TCP/IP, GPIB, USB and the library NI VISA, python.socket, ...). This makes a lot of sense for lab devices that have multiple interfaces (e.g. TTi, Keithleys, ...). I am not sure what we gain for having such generic TL/HL pattern, when the TL is not interchangeable, not configurable and fixed (@michaeldaas an me discussed that recently, too).

[DavidLP]

I recommend to configure your editor in a way that it takes care of the code style. Good editors (pydev, VStudio Code, ...) can do that. When you clean up the formatting issues https://travis-ci.org/github/SiLab-Bonn/basil/jobs/741928925#L5989 it is fine to be merged. You can check for code flaws by typing:

flake8-diff origin/development

[DavidLP]

Also, you see that the CI failed due to code flaws

[coveralls]

Coverage decreased (-1.1%) to 32.447% when pulling 52d54d3 on sensirion_sht85 into 968842a on development.