Get package.xml up to date with 1.1.0

Signed-off-by: Dan Scott <dan@coffeecode.net>
Fix MARC-in-JSON serialization of subfield 0

Work around json_encode()'s inability to express array keys as stringified keys
(and thus objects, in keeping with the MARC-in-JSON specification) in the
_specific_ case of 0, via a (yes) regex.

Now I have *E#(*DSNFSD( problems...

Signed-off-by: Dan Scott <dan@coffeecode.net>