Merge branch 'multi-input' into 'develop'

- command line now accespts multiple options `-d`  (data input)
- SaQC can eat now list of Data-like
- SaQC can eat now list of Flags-like
- duplicate columns in input will overwrite former columns (with same name) and we throw a warning see fist thread why this is like this)

closes #257

See merge request !357