add tests for centring for DenseMatrixData, SparseMatrixData, ScarseMatrixData
add tests for centring for DenseMatrixData, SparseMatrixData, ScarseMatrixData

ExaScience/smurff,ExaScience/smurff,ExaScience/smurff,ExaScience/smurff,ExaScience/smurff,ExaScience/smurff