added comment to trader-details

DSA-64
first test of TraderService.calculateXX
Merge branch 'DSA-64-berechne-preise-sortiment-eines-h' of bitbucket.org:sepm/tu-sepm-dsa into DSA-64-berechne-preise-sortiment-eines-h
adding trader should create sortiment

DSA-64
Merge remote-tracking branch 'origin/DSA-64-berechne-preise-sortiment-eines-h' into DSA-64-berechne-preise-sortiment-eines-h
händlerkategorie fixes
DSA-64
TraderService calculateXX
Merge branch 'DSA-64-berechne-preise-sortiment-eines-h' of bitbucket.org:sepm/tu-sepm-dsa into DSA-64-berechne-preise-sortiment-eines-h