Add Watch Task

[Remco Janssen]

Add a watch task for the libs folder.

[vaporstack]

Added to gulpfile. Created a separate branch (vs) because I changed some things in lib as well.

[vaporstack]

    watch = require('gulp-watch');
//------
gulp.task('watch', ['build'], function () {
    gulp.watch('lib/*.js', ['concat']);
});

[Remco Janssen]

The watch task is in the core of Gulp, so gulp-watch wasn't necessary and added the change to the main Khanyu branch.

The watch task is now in the default task, so now when you do gulp in Terminal it stays watching for file changes. Change any of the files in /lib and it will deploy to the ScriptUI folder.

The build task is manual for now and this will change when we have a proper build workflow in place.