Automatically identify end of ramp-up and beginning of ramp-down process

[1kastner]

Currently, the start date and end date are provided to synthetically generate the data. All reported previews and analyses always take the whole period into account. However, at times it could be more interesting to restrict oneself to the data during the "normal" operations period. Then, the ramp-up and ramp-down period should be neglected when it comes to the estimation of operational figures.

This is supposed to be an additional, optional feature. There might be different results depending on the approach of identification. Thus, by default the figures should be reported as it is the case currently.