Remove FooterHelper and default footer messaging

** Why are these changes being introduced:

* During initial prototyping of this theme, I put together a simple
  helper class to try and figure out how they work, and what they might
  be useful for. At this stage of the project, though, I'm not sure that
  we will have a need for them - so it is time to remove it.

  (The Freedome theme has a suitable example, in the wild, of what a
  helper class might do, by the way)

** Relevant ticket(s):

* https://mitlibraries.atlassian.net/browse/post-69

** How does this address that need:

* This removes the FooterHelper class, the reference to it in the
  config.ini, and the call to it in the page layout template.
* This also removes the entire <footer> element that was part of the
  default page layout, which included a "Build with Omeka S" phrase that
  we don't want to preserve.
* Finally, this updates the Makefile's deploy workflow to remove the
  reference to the now-deleted helper folder.

** Document any side effects to this change:

* This isn't a side effect per se, but if we ever decide to add a
  helper down the road, like with the addition of any other deployable
  folder, we will need to keep the Makefile's deploy steps in sync.

Author: matt-bernhardt

Makefile

@@ -41,5 +41,4 @@ deploy: ## Deploys the theme on a host server
 	rsync --recursive --delete asset/img/ /var/www/html/themes/mitlibraries-theme-omeka/asset/img/
 	rsync --recursive --delete asset/js/ /var/www/html/themes/mitlibraries-theme-omeka/asset/js/
 	rsync --recursive --delete config/ /var/www/html/themes/mitlibraries-theme-omeka/config/
-	rsync --recursive --delete helper/ /var/www/html/themes/mitlibraries-theme-omeka/helper/
 	rsync --recursive --delete view/ /var/www/html/themes/mitlibraries-theme-omeka/view/

config/theme.ini

@@ -7,8 +7,6 @@ theme_link = "https://github.com/MITLibraries/mitlibraries-theme-omeka"
 author_link = "https://libraries.mit.edu"
 omeka_version_constraint = "^4.0.0"
 
-helpers[] = "FooterHelper"
-
 [config]
 elements.banner.name = "banner"
 elements.banner.type = "Omeka\Form\Element\Asset"

helper/FooterHelper.php

@@ -96,9 +96,5 @@ $userBar = $this->userBar();
             </div>
             <?php echo $this->partial('common/footer-site-slim'); ?>
         </div>
-        <footer>
-            <?php echo $this->FooterHelper(''); ?>
-            <span class="powered-by"><?php echo $translate('Powered by Omeka S'); ?></span>
-        </footer>
     </body>
 </html>