Feature: add/remove file with grunt watch

[amitava82]

Instead of creating whole block we could setup grunt watch and listen to added or deleted event and add/remove script.

grunt.event.on('watch', function(action, filepath) {
  if(action == 'added'){
   //add script
  }
  if( action == 'deleted'){
   //remove script
  }
});

[scott-laursen]

Good idea. If you do a pull request I will merge it in.