add driver for SDS011 active laser dust sensor

[MichelRottleuthner]

Contribution description

Adds a driver and SAUL integration for the SDS011 dust sensor for measuring particulate matter concentration.

Testing procedure

Below example is only true for pba-d-01-kw2x, for other boards adapt as needed.
For SAUL use the default test application:

cd tests/saul
USEMODULE=sds011 CFLAGS="-DSDS011_PARAM_UART_DEV=UART_DEV\(1\) -DSDS011_PARAM_PWR_PIN=GPIO_PIN\(3,5\)" make BOARD=pba-d-01-kw2x all flash term

With the provided test:

cd tests/driver_sds011
CFLAGS="-DSDS011_PARAM_UART_DEV=UART_DEV\(1\) -DSDS011_PARAM_PWR_PIN=GPIO_PIN\(3,5\)" make BOARD=pba-d-01-kw2x all flash term

Issues/PRs references

[smlng]

first sweep, looks nice already - only minor coding style issues, check position of braces!

[leandrolanzieri]

Looks really nice. Just a few comments, most of them typos.

[MichelRottleuthner]

@smlng @leandrolanzieri thank you for reviewing! I think all requests should be addressed now

[leandrolanzieri]

All my comments have been addressed. I ran the test and works as expected. Looks good to me.

[leandrolanzieri]

@smlng ping?

[MichelRottleuthner]

@smlng ping

[MichelRottleuthner]

rebased again @smlng ping

[smlng]

in the documentation many functions have a preconditions like <param> != NULL, for these there should be a matching assert in every implementation to verify this during development. This is missing, e.g. in sds011_get_fw_version and others.

[MichelRottleuthner]

@smlng everything addressed now? and may I squash?

[smlng]

all good except one small inconsistency 😬 Please amend directly and squash previous changes as needed, too.

[MichelRottleuthner]

@smlng I fixed the remaining problems reported by murdock and removed the separate thread in the test to make it fit on the small arduinos. So, finally all spaces where they should be?^^