fix: failure of make engine test when a make engine alias contains a modifier. There can be more than one variant per alias via "." e.g. make.extrastuff where make and extrastuff are variants.

Fix up file testing with checkwhatcomp and make epocroot driveletter stripping case insensitive.

FilterCheckComp - checking file existence by component

Merge

release: notes for sbs_filter-related changes

Tests cor check and whatTests cor check and what

fix: make filters work with new default python fix: Make Check filter actually check stuff when run from the filter