Added support for trailing commas within libconfig lists

- Follow-up to 62c5e65d28833c1068d195778c0e3a710acaa104, special thanks
  to Ind
- A trailing comma in a libconfig list (enclosed in parentheses) will no
  longer cause a parse error.
- Updated config files where it makes sense to put a trailing comma

Signed-off-by: Haru <haru@dotalux.com>