How to include Bootstrap icons in ASP.NET MVC4?

How to include Bootstrap icons in ASP.NET MVC4?

Basically after a bunch of work I've finally managed to get up and running
with Bootstrap in my ASP.NET MVC4 project.
Here is my folder structure:

Here is my bundleconfig:
public static void RegisterBundles(BundleCollection bundles)
{
bundles.Add(new ScriptBundle("~/bundles/jquery").Include(
"~/Scripts/jquery-{version}.js"));
bundles.Add(new ScriptBundle("~/bundles/bootstrapjs").Include(
"~/Scripts/bootstrap.js"));
bundles.Add(new ScriptBundle("~/Content/bootstrapcss").Include(
"~/Content/bootstrap.css",
"~/Content/bootstrap-responsive.css"));
}
However when I try to add an HTML element with an icon:
<button type="submit" class="btn"><i class="icon-search"></i></button>
The icon does not appear.