Merge pull request #303 from tahitiangabriel/bootstrap3

Bootstrap3 - Navbar : Add navbar's markupId in the data-target of the collaspe button instead of the ".navbar-ex-collapse"
Issue #307 - Add test asserting that invisible input doesn't render surrounding markup
Upgrade to Wicket 6.13.0

Upgrade wicket-webjars to 0.3.3
Use TagTester for Html5PlayerTest to solve some whitespace issues when building on Windows
DateTextFieldConfig "todayHighlight" must be false by default
see
http://bootstrap-datepicker.readthedocs.org/en/latest/options.html#todayhighlight