Rewrite reviewing and add flagging curves.
Rewrite reviewing and add flagging curves.

* Flag curves: Force curves now can be flagged (internally marked)
  based on some specified criteria (with user parameters). Following
  criteria are implemented:
  * If the calculated (fitted) deflection sensitivity deviates from
    the one in data header by a certain amount (expressed in
    percent deviation)
  * If the calculated brush height is negative
  * If the brush height deviates from the average one by a certain
    amount (expressed in multiples of the standard deviation)
* Flag criteria can be extended by adding additional functions
* Flagged curves can be marked on the image graphs
* Option to review all curves, or only flagged curves (automatically
  accepting all non-flagged curves)
* Review function now takes always a filter wave which defines
  which curves should be reviewed
* Show current curve in review as marker on image graphs
* Remove exponential fit values from review dialog, add deflection
  sensitivity values instead

jhyot/afm-forcecurve-analysis