Culture & language searches made more user-friendly, basic error handling

Culture trait can only be selected after choosing a category
Language subfamilies can only be selected after choosing a family (and if they exist - subsubfamily will not show up if no subsubfamilies can be chosen)

Also some in-progress code for select all (works, just need to work on deselect all and figuring out how to update the # of variables selected).

Not sure why this says 346 files were changed?