Fixed import error in StatisticsPointList.py

[jemajet]

The change in this commit was causing import ClearMap.Compile as outlined in the installation docs to fail with the error

>>> import ClearMap.Compile
ClearMap.ImageProcessing.Binary.Filling
ClearMap.ImageProcessing.Clipping.Clipping
ClearMap.ImageProcessing.Differentiation.Hessian
ClearMap.ImageProcessing.Filter.Rank
ClearMap.ImageProcessing.Thresholding.Thresholding
ClearMap.ImageProcessing.Tracing.Trace
ClearMap.ParallelProcessing.DataProcessing.ArrayProcessing
ClearMap.ParallelProcessing.DataProcessing.ConvolvePointList
ClearMap.ParallelProcessing.DataProcessing.DevolvePointList
ClearMap.ParallelProcessing.DataProcessing.MeasurePointList
ClearMap.ParallelProcessing.DataProcessing.StatisticsPointList
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/ClearMap2/ClearMap/Compile.py", line 48, in <module>
    import ClearMap.ParallelProcessing.DataProcessing.statistics.StatisticsPointList as spl
  File "/ClearMap2/ClearMap/ParallelProcessing/DataProcessing/statistics/StatisticsPointList.py", line 29, in <module>
    import ClearMap.ParallelProcessing.DataProcessing.StatisticsPointListCode as code
ModuleNotFoundError: No module named 'ClearMap.ParallelProcessing.DataProcessing.StatisticsPointListCode'

This error was introduced by moving the StatisticsPointList into a folder, but didn't update the import path in the py file. This pull request adds that fix.