The tab-completion code treated all matches as case-insensitive because that's how Microsoft Windows handles filenames. This is now inadequate, as shell builtins, functions and aliases are case sensitive. Modify the treatment of case-sensitivity in tab completion: - Track whether each potential match is case-insensitive (filename) or case-sensitive (shell builtin, function or alias). - When comparing matches use a case-insensitive comparison if either value is a filename. Otherwise use a case-sensitive comparison. Adds 64 bytes.