Proposal for decoding of GS1 compliant datamatrix codes

Hi together,

I often scan GS1 compliant datamatrix codes with zxing (which is lovely, btw.). Unfortunately they were not decoded into the different application identifiers (with their values).

I added a parser to decode and format the content. The major changes are in the core library. 
I'm a bit uncertain if decoding countries and currencies from the three digit iso codes is a good idea, as they are more or less likely to change.

If the code lacks of further tests or needs some tweaking to meet your quality standards, please let me know. Unfortunately I formatted the core\pom.xml what messed it up a bit in the diff :-(.


Cheers,

Melchior

PS: I noticed that your primary repo is a google svn. I don't have a google login (and it's not likely I'll have one in the future), so I'm not able to commit the patch there.