Bug in boilerplate-mochachai functional tests

Bug in boilerplate-mochachai/tests/2_functional-tests.js:

1) Functional Tests
       e2e Testing with Zombie.js
         "Famous Italian Explorers" form
           #example - submit the input "surname" : "Polo":
     TypeError: browser.fill(...).pressButton is not a function
      at Context.<anonymous> (tests/2_functional-tests.js:216:12)
  2) Functional Tests
       e2e Testing with Zombie.js
         "Famous Italian Explorers" form
           submit "surname" : "Colombo" - write your e2e test...:
     TypeError: browser.fill(...).pressButton is not a function
      at Context.<anonymous> (tests/2_functional-tests.js:247:12)

browser.fill() returns a promise under the current version of Zombie.

Should be:

browser.fill();
browser.pressButton();

or

browser
  .fill()
  .then(() => browser.pressButton());

I was going to submit a pull request for this issue, but then I saw someone already did 14 months ago. I spent one hour figuring this out. I think it is time to fix this one, please!