this changes all api calls to respect the flags for tor and tor-port

- config now has TorPort method to return flag value if set, or default
- api now only has newClient, this creates a tor client when flag is
present. does not need to be exported anymore
- no methods take a tor argument as no longer needed
- all commands now share the same behaviour logging tor messages
- api.torClient was removed as not used anywhere
- all calls to api.newClient now check for and return the error
- api.HandlePost was removed as redundant of api.DoPost