Add magic.Version constant that denotes current version of the magic package.

Signed-off-by: Krzysztof Wilczynski <krzysztof.wilczynski@linux.com>
Fix. Revert 06de40ef8f28adf500e752cff1026ef61da1b1ac.

Remove the magic.Version constant as it clashes with other functions.

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