It accepts a va_list and will be used by QError. Also simplifies
the code a little, as the other qobject_from_() functions can
use it.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This introduces qobject_to_json which will convert a QObject to a JSON string
representation.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This provides a QObject interface for creating QObjects from a JSON expression.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>