PercentileGridSampler now gives correct sampling.
PercentileGridSampler now gives correct sampling.

In madai_generate_trace, PercentileGridSampler now has its
SetNumberOfSamples() method called only after SetInactiveParameters()
has been called for the last time.

> https://git.cs.unc.edu/redmine/MADAI/issues/450
> Issue450_IncorrectGridSampling

chunshen1987/DistributionSampling,chunshen1987/DistributionSampling,chunshen1987/DistributionSampling,chunshen1987/DistributionSampling,chunshen1987/DistributionSampling,chunshen1987/DistributionSampling