isEmpty doesn't check for empty objects

[Grohden]

trafficstars

I'm currently having problems to show my placeholder, my default model is a empty object, and i need it that way. But ui select doesn't validate empty objects.

Here are the lines that validate that: https://github.com/angular-ui/ui-select/blob/32829a39e8efe7f94de049c6b529c23fedfc6686/dist/select.js#L366-L368

A equals comparation would solve that angular.equals(ctrl.selected, {}) and show the placeholder.