REST is now able to detach from the current shell window

I have added a new feature to detach REST from the current shell window. During the process, we call out the pause menu by pressing p. Then we press d. You will see the detach menu.

The detached REST process will be an orphan process, which could be seen from ps. By detaching REST, one can close the shell window without exiting it. One can also start multiple REST manager in a same window.

The output would be redirected to the file you specified. By default it will be redirected to /dev/null

Ok, it is good to have this feature in REST. It is also handy to use GNU screen command to detach and run simultaneously several REST processes.