0-1 normalization

[holgerteichgraeber]

Implement 0-1 normalization as an option in run_clust().
This would entail a change in naming of the ClustInputData struct:
All normalization methods are of the form (A-x)/y, where x is \mu and y is \sigma for z-normalization, and x is min(A), and y is max(A)-min(A) for 0-1 normalization.
Thus, need to replace mean and sdv with more generic terms.