Change the functioning of the DSS

[SanderNielen]

We want the DSS to align with the various MCDA options that exist. Currently, there seem to be a few misalignments or misinterpretations.

• 1. It seems that sampling_mode is only used when weight_mode=="group". How to also use it for guiding the sampling of criteria values?
• 2. Support qualitative criteria by allowing to convert them to ordinal numbers (predefined).
• 3. Allow for ordinal ranking of groups and criteria (not only pairwise preferences). In the background, the ranking can still be translated to pairs (assuming an intensity of 1).
• 4. Introduce a new weight_mode, wher the user can specify a weight for each criterion. The exisiting weight_mode=="flat" automatically gives all criteria the same weight.
• 5. Don't ask the user to enter alpha and n_samples values.
• 6. Check if the group weights are needed when the sampling_mode=="random"?

These six items can be addressed by changing the MCDA functions, or the code related to the user forms.