Navbar: Implement Classes Option

[cgack]

This includes the new navbar widget from the navbar review branch.

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[cgack]

@arschmitz ready for review when you get a chance

[arschmitz]

Don't use self this break in some contexts self has special meaning window.self === window instead use var that = this;

[cgack]

@arschmitz I made some changes. ready for another round when you get a chance

[dt1973]

Sorry to interject, but will this prevent jQM from inserting classes into my navbar elements such as h2? I'm using the structure only CSS, and right now I have to wrap all my stuff inside <div></div> to prevent this from happening.

[arschmitz]

@dt1973 can you open an issue explaining your issue with a jsbin example and we will be happy to take a look and consider this case.

[arschmitz]

use this

[cgack]

Closing with f3bd7c4 landing on 1.5-dev