code: function urlBuilder(params) {
    var builtUrl = params.base;
  
    builtUrl += '?';
  
    if (params.apiKey) {
      builtUrl += 'key=' + params.apiKey + '&';
    }
  
    if (params.client) {
      builtUrl += 'client=' + params.client + '&';
    }
  
    if (params.libraries.length > 0) {
      builtUrl += 'libraries=';
  
      params.libraries.forEach(function(library, index) {
        builtUrl += library;
  
        if (index !== params.libraries.length - 1) {
          builtUrl += ',';
        }
      });
  
      builtUrl += '&';
    }
  
    if (params.language) {
      builtUrl += 'language=' + params.language + '&';
    }
  
    if (params.version) {
      builtUrl += 'v=' + params.version + '&';
    }
  
    builtUrl += 'callback=' + params.callback;
  
    return builtUrl;
  }
docs: urlBuilder
  
  @param  {object} params
  @param  {string} params.base       the base url
  @param  {array}  params.libraries  an array of the libraries to be requested
  @param  {string} params.callback   the callback function
  
  @return {string}