Rename get_available_themes to get_user_accessible_themes to make it clearer

Signed-off-by: Andrew Robert Nicols <andrew.nicols@luns.net.uk>

htdocs/lib/mahara.php

@@ -548,7 +548,7 @@ function get_all_themes() {
  * institution specific are returned.
  * @return array subdir => name
  */
-function get_available_themes() {
+function get_user_accessible_themes() {
     global $USER;
 
     $themes = array();

htdocs/view/blocks.php

@@ -123,7 +123,7 @@ $extraconfig = array(
 
 // Set up theme
 $viewtheme = $view->get('theme');
-$allowedthemes = get_available_themes();
+$allowedthemes = get_user_accessible_themes();
 if ($viewtheme && $THEME->basename != $viewtheme) {
     $THEME = new Theme($viewtheme);
 }