Joachim Pouderoux authored Nov 29, 2013 and Tristan Coulange committed Dec 19, 2013

Add the support of Robust PCA computation in vtkPCAStatistics.
This is performed by computing median instead of mean in the
vtkMultiCorrelativeStatistics class (done when turning
on the MedianAbsoluteVariance flag). Support is also done
in the parallel version of the algorithms.
Add 2 tests for this new robust implementation.

Change-Id: If91813722c7528b96e6594a3b6e21ebcf3e6b455