Make job file list columns configurable and allow customInfo values to be shown #525

At the moment the Jobs file list shows a fixed set of metadata columns (height, layer height, filament usage, print time, simulated time, generated by). They are only dropped when no file in the current directory provides a value, so there is no way to hide a column that is not of interest or to get these columns in the Explorer, which shows none of them.

Make the displayed columns selectable per file list. In addition, customInfo from M36 is currently only available as a row tooltip and in the file info dialog; allow individual customInfo keys to be picked as columns too. That is mainly of interest for OEMs embedding their own fields in sliced files.