PIA metrics: should we store all results

[julianu]

In the current HDF5 export, only the "real" metrics (and PPM distribution of FDR valid targets) is stored.
Originally, there was also the complete results on PSM, peptide and protein level (as zipped file). For now, I did not create this anymore. Do we still need this?

Actually, there were also some differences:

• PSMs were not filtered, but all results
• peptides and proteins were FDR filtered already