code: function loadFile(filepath, defaultObj) {
    defaultObj = defaultObj || {};
  
    if (!isFile(filepath)) { return defaultObj; }
  
    var extension = path.extname(filepath).replace(/^\./, '');
    var contents = supportedExtensions[extension](filepath);
  
    return assign({}, defaultObj, contents);
  }
docs: Loads a file, if it exists. If it doesn't, then return the default object or empty object