new global gDirs for default directories and filters; rm warnings from file loaders

standardize file save dialogs

disentangle ProjectManager from new src pair Dirs

rm all handling of warnings; just throw a runtime_error if something fails. This saves us lots of compilcations.

added 6 commits

• 6f33bbf0 - gDIrs + script|data_import_dir
• a8d48154 - expand 'auto'
• be74faaf - rm warnings mechanism from load datafiles
• fd71e7d9 - rm class ReadResult
• 229e994e - rm MessageService
• 6111aad9 - rm DeserializationException

Compare with previous version

changed title from new global gDirs for default directories and filters to new global gDirs for default directories and filters; rm warnings from file loaders

changed the description

enabled an automatic merge when the pipeline for 6111aad9 succeeds

mentioned in commit 298f921f

merged