Develop histfactory stat error handling

Release notes

• [SFramework] Many smaller improvements and fixes to statistics code
• added --wait argument for submission scripts to keep submission loop running until all jobs are done or an error is detected
• [SFramework] ActionImportResults: allow importing a comma separated list of results files at once

Details

Branch is still in active use by the HWW properties analysis and will therefore have to continue existing (more developments are expected, hence another MR will follow at some later point)

(CI failures are only due to plotting tests not finding reference artifacts, this MR has no direct relation to the regular plotting)