v0.2.1 - @ escapes, and temp files become temp

Changed

• "@" in input file names must now be escaped using "@" ("@@") instead of "\" ("\@"). This means that, on Windows, paths can now be supplied in the default format (with "\" as separator, instead of "/").
• Verbose info prints are now hidden by default. Use "-v" or "--verbose" to see them.

Fixed

• The temporary list file (containing intermediate clip file names for concatenation) is now actually placed in a temporary directory, and doesn't pollute the output file's directory.