chore(package.json): update grunt-contrib-connect and load-grunt-config
fix(dropdown): transclude options content manually

As of Angular.js v1.2.18, nested transclusion with ng-repeat wasn't
binding to the correct scope (see angular/angular.js#7842). To fix that,
we should manually transclude the content of options and then, finally,
compile the options with ng-repeat.

Fixes #14