Angular Dropdown menu:
https://www.codementor.io/angularjs/tutorial/create-dropdown-control
https://angular-ui.github.io/bootstrap/
https://github.com/jseppi/angular-dropdowns (https://jsfiddle.net/jseppi/cTzun/142/embedded/result/)
Angular Left menu:
http://stackoverflow.com/questions/18599753/vertical-navbar-using-bootstrap-and-angular (http://plnkr.co/edit/UBBq7V8mdyqllBHdwegY?p=preview)
Angular Subheader
http://codepen.io/svswaminathan/pen/MYBrgM
