Looser matching of filenames in FIAD

-- case-insensitive
-- allow spurious ".bin" suffix, e.g. from web browser
Make disk image selector browsing less confusing
Allow more convenient keyword-based module search
Support adding modules at runtime; add RPK support
Move module scanning logic to machine
Refactor module selector
Organize module selector into tree to allow distinct DBs
Improve module refresh, DB management UI, stock icons
Clean warning
Shorten module list label
Move utility