It would be nice if the debug console had a little help page of itself, to describe the syntax to issue commands (also the nested ones), and a disclaimer that usage can be dangerous.

Maybe add a debug-console-only command like help that shows how to use nested commands and potentially other advanced tricks, and add 'for more information on using this console type XXX'.

See also:
- https://github.com/bitcoin/bitcoin/pull/7783#issuecomment-248274853
- https://github.com/bitcoin/bitcoin/issues/8544#issuecomment-240970925
- #8912 Console command paths cannot be specified correctly with backslashes
}
                    if ((state == STATE_EATING_SPACES_IN_BRACKETS || state == STATE_ARGUMENT) && ch == ',')
                    {
                        state = STATE_EATING_SPACES_IN_ARG;
                        break;
                    }
                    state = STATE_EATING_SPACES;
                    break;
                default: curarg += ch; state = STATE_ARGUMENT;
            }
                break;
            case STATE_SINGLEQUOTED: 
                switch(ch)
            {
                case '\'': state = STATE_ARGUMENT; break;
                default: curarg += ch;
            }
                break;
            case STATE_DOUBLEQUOTED: 
                switch(ch)
            {
                case '"': state = STATE_ARGUMENT; break;
                case '\\': state = STATE_ESCAPE_DOUBLEQUOTED; break;
                default: curarg += ch;
            }
                break;
            case STATE_ESCAPE_OUTER: 
                curarg += ch; state = STATE_ARGUMENT;
                break;
            case STATE_ESCAPE_DOUBLEQUOTED: