move-xblock-breadcrumb.underscore

<nav class="breadcrumbs" aria-label="Course Outline breadcrumb">
    <% _.each(breadcrumbs.slice(0, -1), function (breadcrumb, index, items) { %>
        <ol class="bc-container bc-<%- index %>">
            <li class="bc-container-content">
                <button class="parent-nav-button" data-parent-index="<%- index %>">
                    <%- breadcrumb %>
                </button>
                <span class="fa fa-angle-right breadcrumb-fa-icon" aria-hidden="true"></span>
            </li>
        </ol>
    <% }) %>
    <ol class="bc-container bc-<%- breadcrumbs.length - 1 %> last">
        <li class="bc-container-content">
            <span class="parent-displayname"><%- breadcrumbs[breadcrumbs.length - 1] %></span>
        </li>
    </ol>
</nav>