[WIP] Convert docs to reST

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we had that for historical reasons: we used debian packaging and the debian configuration dialog used to create the paramters.yml only allows string values, not list formats. it stayed in even though we don't use that debian thingy anymore. 

i guess https://github.com/Incenteev/ParameterHandler/ can handle array parameters? if not, that would be a good reason to keep supporting comma separated lists.