shakedex: query finalize tx when not found in db

[chikeichan]

This fixes an issue where if user finalize an exchange transfer in my domain instead of exchange, bob will look for the the finalize coin from the full node.

TODO:

• write exchagne finalize to exchange db even when user is finalizing it from "My Domain" view

[chikeichan]

Now shakedex service always query finalize tx by transfer hash + transfer name. Less dependent on what's written to the db.