Parse getStatus as JSON not XML
On dogtagpki/pki master XML is being replaced by JSON, getStatus will
return JSON in PKI 11.0+
The PR for dogtagpki/pki that makes this change necessary is:
https://github.com/dogtagpki/pki/pull/3674
Reviewed-By: Rob Crittenden <rcritten@redhat.com>
Reviewed-By: Francois Cami <fcami@redhat.com>