Don't catch Magic::Error and always raise on errors coming from libmagic.

This is to make it more aligned with the standard library, where
file and I/O related errors would raise an appropriate exception.

Signed-off-by: Krzysztof Wilczynski <krzysztof.wilczynski@linux.com>
Don't catch Magic::Error and always raise on errors coming from libmagic.

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