Sp8.sc1.changeable parameters for prediction

The parameters for the number of datapoints to make the prediction on and the number of predicted points are nr_values and nr_preds respectively. So a request could look like this:

NEW WAY: localhost:8000/streams/1/_analyse?nr_values=100&nr_preds=10

OLD WAY(still works): localhost:8000/streams/1/_analyse  

In the old way the nr_values and nr_preds will be defaulted to 50 and 25. Just as it worked before.