going from one page with bar-tab to another without bar-tab, bar tab dissapear
From the doc:
`This will use push to replace everything in the .content div with the .content of two.html. It will also update .bar-title and .bar-tab if you have them on both pages.`

As of right now, if two.html doesn't have a .bar-tab, then the existing .bar-tab of one.html got removed. Is this by design?
