Added a data.more variable.

This way you can display separately your excerpt (kind of heading) and your content, e.g. by doing :
<section class="post-content">
  <% if (post.excerpt){ %>
    <header>
      <%- post.excerpt %>
    </header>
  <%- post.more %>
  <% } else { %>
    <%- post.content %>
  <% } %>
</section>
updating lib/model/schema.js to match the more var.
Merge pull request #830 from lebarde/data.more

Added a data.more variable.