Bug 1049916 - Create Firefox Accounts smoke tests to validate user authe...

...ntication R=spenrose
Per your suggestion, I've made the asserts more idiomatic (removing !== -1) and offloaded emailEnterNew, etc. to lib functions.  I've left asserts in for each step, since we're testing screen flow, but let me know if my usage of asserts seems excessive:
  test('should walk flow for: Firefox Accounts (new user)', function () {
    assert.ok(app.enterEmailNew(selectors.emailInput));
    assert.ok(app.onClick(selectors.moduleNext));
    assert.ok(app.onClick(selectors.moduleNext));
    assert.ok(app.enterPasswordNew(selectors.pwInputPostCOPPA));
    assert.ok(app.onClick(selectors.moduleNext));
    assert.ok(app.onClick(selectors.moduleDone));
  });