Inconsistency in support of Data Matrix codes

[rmutalik]

In pyzbar's pyzbar.py file, in the documentation for the decode function, it states, "Decodes datamatrix barcodes in image."

However, in this closed issue, @quicklizard99 refers a user to use pylibdmtx to read Data Matrix codes.
#80

I did not see Data Matrix mentioned in the ZBarSymbol enums in wrapper.py. I also am aware that pyzbar and pylibdmtx were created by the same organization.

Does pyzbar officially support Data Matrix symbols? That needs to be clarified and updated in the documentation to reflect that.