Refs #10432. Using straight-forward detector index
Refs #10432. Adding tests to PoldiAnalyseResiduals
Refs #10432. Completing PoldiAnalyseResiduals, added tests
Revert "Refs #10432. Removing magic number from CostFuncLeastSquares"

This reverts commit e41045891877341621472360650ff412e8103f52.
Revert "Refs #10432. Small changes to PoldiCalculateSpectrum2D"

This reverts commit 8112591b9bd87638513d306d967f62384de60709.