[ci skip] Update TODO, CHANGES and CHANGES.rdoc files.

Signed-off-by: Krzysztof Wilczynski <krzysztof.wilczynski@linux.com>
[ci skip] Update TODO file.

Signed-off-by: Krzysztof Wilczynski <krzysztof.wilczynski@linux.com>
Add support for MAGIC_CONTINUE flag and return an array for multiple results when appropriate.

This concerns Magic#file, Magic#buffer and Magic#descriptor.

Signed-off-by: Krzysztof Wilczynski <krzysztof.wilczynski@linux.com>
Update documentation a tiny little bit.

Signed-off-by: Krzysztof Wilczynski <krzysztof.wilczynski@linux.com>