Suggestion: Support Watchify

[Thr1ve]

Hello! Would it be possible to integrate Watchify when using Gulp ? For instance, https://github.com/greypants/gulp-starter :

his browserify gulp task file:

/*Bundle javascripty things with browserify!
If the watch task is running, this uses watchify instead
of browserify for faster bundling using caching.
*/
var browserify   = require('browserify');
var watchify     = require('watchify');
var bundleLogger = require('../util/bundleLogger');
var gulp         = require('gulp');
var handleErrors = require('../util/handleErrors');
var source       = require('vinyl-source-stream');

gulp.task('browserify', function() {

var bundleMethod = global.isWatching ? watchify : browserify;

var bundler = bundleMethod({
    // Specify the entry point of your app
    entries: ['./src/javascript/app.coffee'],
    // Add file extentions to make optional in your requires
    extensions: ['.coffee', '.hbs'],
    // Enable source maps!
    debug: true
});

var bundle = function() {
    // Log when bundling starts
    bundleLogger.start();

    return bundler
        .bundle()
        // Report compile errors
        .on('error', handleErrors)
        // Use vinyl-source-stream to make the
        // stream gulp compatible. Specifiy the
        // desired output filename here.
        .pipe(source('app.js'))
        // Specify the output destination
        .pipe(gulp.dest('./build/'))
        // Log when bundling completes!
        .on('end', bundleLogger.end);
};

if(global.isWatching) {
    // Rebundle with watchify on changes.
    bundler.on('update', bundle);
}

return bundle();
});

see also: https://github.com/gulpjs/gulp/blob/master/docs/recipes/fast-browserify-builds-with-watchify.md#fast-browserify-builds-with-watchify

Also: -Could adding BrowserSync like in greypants' gulp-starter be worth considering? -It seems like the ".tmp/" equivalent is the "build/" in Gulp. Would it be improper to rename the "tmp" directory to "build" when selecting Gulp?

Trying to get a pull request ready, but I'm a bit new / unexperienced so it may take me awhile...still trying to wrap my head around pretty much everything here... Please yell at me if I've been improper/ignorant in any way with this.