Changes in QMBCFN 1.30:
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- Added a feature that allows to exclude points from the fit without having to change the data file / functions / derivatives.
More details:
In the Model Functions Tab of QMBCFN, each row now has a checkbox controlling whether the function/data point i
will be included in the fit. Note that, as in previous QMBCFN versions, the data file must always contain all data points i
listed in the Model Functions Tab (and only those), irrespective of whether some points are deactivated. However, deactivated data points
are not used in the fit. This means that the corresponding rows and columns in the data correlation matrix C are removed
(before the inversion), and all sums over i and j in the calculation of chi^2 etc. exclude the deactivated values of the indices.

- When loading session files, a warning message is now given if the session file version is newer than the program version (may be useful in the future)

- restore "waiting cursor" to "normal cursor" before message boxes are displayed