Fix hidden SnippetsCtrl in examples site page

[jwasilgeo]

The SnippetsCtrl depends on the leftNavStyle binding, which worked when the index.html page had only the ExamplesCtrl and then SnippetsCtrl. It appears that the nesting is slightly off here under PatternsCtrl, since SnippetsCtrl leftNavStyle value should line up with parent leftNavStyle in ExamplesCtrl. The effect is that the snippets tabs are always hidden when browsing example pages.

[tomwayson]

thanks for finding and fixing that @jwasil!