Deprecate CloseTransaction protobuff message
Deprecated the associated CloseTransaction and CloseTransactionReply
protobuff messages and changed the message classes to extend
VersionedExternalizableMessage. Backwards compatibility with pre-boron
is maintained. Related code was modified accordingly.
While the backend sends back the CloseTransactionReply, the transaction
front-end doesn't actually use it so I removed the protobuff-related
code in CloseTransactionReply as it doesn't matter which serialized
version is returned.
Change-Id: I42946bbb38c5ff84d05ee0578d8ca9c8f124d5ed
Signed-off-by: Tom Pantelis <tpanteli@brocade.com>