PileUpUtils: fix run and lumi profile generation
Fix run and lumi profile generation where mu values may be the same by accident (as in case with flat profiles). The step number should override the mu so that it is used as the sorting criterium (we use the same code as for standard pile-up jobs). Also sort the resulting profile by step.
Sorry, I also fixed some whitespace inconsistencies when reading the code in detail to spot the issues.