added option for autonav templates to ignore exclude_nav attributes (useful for breadcrumb menu)
avoid caching of securimage

http://www.concrete5.org/developers/bugs/5-6-0-2/securimage-only-reloads-the-first-time-it-is-clicked-on/
Fix custom style lost after adding layout

This pull request fixes the fact that custom styles are lost when
adding a layout to a page with blocks having custom styles.

Bug tracker: http://www.concrete5.org/index.php?cID=394701
remove duplicate send_notification_from field

can't save send_notification_from because there are two instances of it
access different field, depending on mode
Fix closing <a> tag
Add missing </strong>
Add missing </strong>
Add missing </strong>
Add missing </strong>
Add missing </strong>
Add missing </strong>
Add missing </span>
Add missing </div>
Close the open h3 instead of h2
Add missing </div>
Add missing </div>
Fix closing <th> and <td>
Remove extra </strong>
Let concrete5 know that ogg, ogv, webm are videos