code: def do_db(self, arg):
          
          self.print_memory_display(arg, HexDump.hexblock)
          self.last_display_command = self.do_db
docs: [~thread] db <register> - show memory contents as bytes
          [~thread] db <register-register> - show memory contents as bytes
          [~thread] db <register> <size> - show memory contents as bytes
          [~process] db <address> - show memory contents as bytes
          [~process] db <address-address> - show memory contents as bytes
          [~process] db <address> <size> - show memory contents as bytes