QPID-4630: HA Fix starting from persistent store.
Reengineered code for converting a Variant to a FieldValue by reinstating
code previously removed.
QPID-4626: Amqp 0-10 Message getProperty() does not correctly return booleans
- Add codec function to convert FieldValue to Variant to support this change
QPID-4626: Amqp 0-10 Message getProperty() does not correctly return booleans
- Improve amqp 0-10 message property handling to correct deal with
  floats/double and bools.