I'm a newbie ruby on rails developer. I've just created my first application and made use of the the bootstrap carousel. Now, I want to add some javascript. My application does not have any custom javascript at this point. What I want to do is when the left or right button on the carousel is pressed, I want an alert to pop up. Preferably, I want to include my javascript file in the /assets/javascript directory. The purpose of this is to just learn how to add new javascript files in my application.