Reworked collections show title, description, refs #9319

Reworked the positioning of the collections show title and description, switched out the folder icon, and made the descriptions metadata table a description list.
How about DRYing out this view a bit like so:

```ruby
    <div itemscope itemtype="http://schema.org/CollectionPage" class="row">
      <div class="col-sm-9 pull-right"><!-- class="column second"> -->
        <header>
          <h1><%= @collection.title %></h1>
          <p class="collection_description"><%= @collection.description %> </p>
        </header>
      <% unless has_collection_search_parameters? %>
        <%= render partial: 'collections/show_descriptions', locals: { generic_file: @collection } %>
      </div><!-- /columns second -->
      <div class="col-sm-3">
        <%= render partial: 'collections/media_display', locals: { generic_file: @collection } %>
        <%= render partial: 'collections/show_actions' %>
      <% end %>
      </div>
    </div> <!-- /columns two-b -->

<%= render 'sort_and_per_page' %>

  <h2><%= has_collection_search_parameters? ? 'Search Results within ' : 'Items in ' %>this Collection</h2>

<%= render partial: 'search_form'%>
<%= render_document_index @member_docs %>

<%= render partial: 'paginate' %>
```