another question: what is this part doing + is it necessary if I just want the filesystem/browsersync functionality?

// File paths to various assets are defined here.
var PATHS = {
  assets: [
    'src/assets/**/*',
    '!src/assets/{!img,js,scss}/**/*'
  ],
  sass: [
    'bower_components/foundation-sites/scss',
    'bower_components/motion-ui/src/'
  ],
  javascript: [
    'bower_components/jquery/dist/jquery.js',
    'bower_components/what-input/what-input.js',
    'bower_components/foundation-sites/js/foundation.core.js',
    'bower_components/foundation-sites/js/foundation.util.*.js',
    // Paths to individual JS components defined below
    'bower_components/foundation-sites/js/foundation.abide.js',
    'bower_components/foundation-sites/js/foundation.accordion.js',
    'bower_components/foundation-sites/js/foundation.accordionMenu.js',
    'bower_components/foundation-sites/js/foundation.drilldown.js',
    'bower_components/foundation-sites/js/foundation.dropdown.js',
    'bower_components/foundation-sites/js/foundation.dropdownMenu.js',
    'bower_components/foundation-sites/js/foundation.equalizer.js',
    'bower_components/foundation-sites/js/foundation.interchange.js',
    'bower_components/foundation-sites/js/foundation.magellan.js',
    'bower_components/foundation-sites/js/foundation.offcanvas.js',
    'bower_components/foundation-sites/js/foundation.orbit.js',
    'bower_components/foundation-sites/js/foundation.responsiveMenu.js',
    'bower_components/foundation-sites/js/foundation.responsiveToggle.js',
    'bower_components/foundation-sites/js/foundation.reveal.js',
    'bower_components/foundation-sites/js/foundation.slider.js',
    'bower_components/foundation-sites/js/foundation.sticky.js',
    'bower_components/foundation-sites/js/foundation.tabs.js',
    'bower_components/foundation-sites/js/foundation.toggler.js',
    'bower_components/foundation-sites/js/foundation.tooltip.js',
    'src/assets/js/**/*.js',
    'src/assets/js/app.js'
  ]
};