NEW: optionally include parent theme css

Bug 1465107: Use Bootstrap CSS Framework

Change-Id: I59856e71b5aeba04474a017c4fd9d381c1ae56ac

htdocs/interaction/forum/index.php

@@ -70,7 +70,7 @@ if ($forums) {
                     'type'  => 'button',
                     'usebuttontag' => true,
                     'class' => 'btn btn-default btn-xs',
-                    'value' => $forum->subscribed ? '<span class="fa fa-lg fa-times prs text-danger"></span> ' . get_string('Unsubscribe', 'interaction.forum') : '<span class="fa fa-lg fa-star prs text-primary"></span> ' . get_string('Subscribe', 'interaction.forum'),
+                    'value' => $forum->subscribed ? '<span class="fa fa-lg fa-times prs text-danger"></span> ' . get_string('Unsubscribe', 'interaction.forum') : '<span class="fa fa-lg fa-star prs text-success"></span> ' . get_string('Subscribe', 'interaction.forum'),
                         // 'help' => $i == 0 ? true : false
                     'help' => false
                     ),

htdocs/interaction/forum/topic.php

@@ -78,7 +78,7 @@ if ($membership && !$topic->forumsubscribed) {
                'type'  => 'button',
                'usebuttontag' => true,
                'class' => 'btn btn-default',
-               'value' => $topic->topicsubscribed ? '<span class="fa fa-times fa-lg text-danger prs"></span>'. get_string('unsubscribefromtopic', 'interaction.forum') : '<span class="fa fa-star fa-lg text-primary prs"></span>' . get_string('subscribetotopic', 'interaction.forum'),
+               'value' => $topic->topicsubscribed ? '<span class="fa fa-times fa-lg text-danger prs"></span>'. get_string('unsubscribefromtopic', 'interaction.forum') : '<span class="fa fa-star fa-lg text-success prs"></span>' . get_string('subscribetotopic', 'interaction.forum'),
                'help' => false
             ),
             'topic' => array(

htdocs/interaction/forum/view.php

@@ -182,7 +182,7 @@ if ($membership) {
                 'type' => 'button',
                 'usebuttontag' => true,
                 'class' => 'btn btn-default',
-                'value' => $forum->subscribed ? '<span class="fa fa-lg fa-times prs text-danger"></span> ' . get_string('unsubscribefromforum', 'interaction.forum') : '<span class="fa fa-lg fa-star prs text-primary"></span> ' .  get_string('subscribetoforum', 'interaction.forum'),
+                'value' => $forum->subscribed ? '<span class="fa fa-lg fa-times prs text-danger"></span> ' . get_string('unsubscribefromforum', 'interaction.forum') : '<span class="fa fa-lg fa-star prs text-success"></span> ' .  get_string('subscribetoforum', 'interaction.forum'),
                 'help' => false
             ),
             'forum' => array(