Transaction binary serialization should support new (NAI-based) storage and optionally legacy form for backward compatibility

This change is specific to following scenarios:

binary serialization impacts signature generation (done at client side), so authorization checks shall be extended to support 2 cases
cli_wallet shall be extended to allow optional generation and signinig transactions in NAI form. This is also related to issue #287 (closed)
legacy serialization must be supported for old blocks where any storage cannot be changed
new and optionally legacy serialization must be supported during P2P communication where incoming binary buffer can contain one of versions.