Use the consolidate function for min or max series

When the function maxSeries or minSeries is called, the consolidate function
'min' or 'max' was added to the TimeSeries created in order to have a better graph.

Also, the aggregation function of the whisper serie is retrieved, so
the TimeSerie could be created with the good consolidate function
Take the aggregation method of whisper just for min or max
Merge branch 'f_consowhisper'

* f_consowhisper:
  Take the aggregation method of whisper just for min or max
  Use the consolidate function for min or max series