Show tips when implementing an exercise

app/views/exercises/_tips_content.html.slim

@@ -0,0 +1,13 @@
+- content_for :head do
+  // Force a full page reload, see https://github.com/turbolinks/turbolinks/issues/326.
+     Otherwise, code might not be highlighted correctly (race condition)
+  meta name='turbolinks-visit-control' content='reload'
+  = javascript_pack_tag('highlight', 'data-turbolinks-track': true)
+  = stylesheet_pack_tag('highlight', media: 'all', 'data-turbolinks-track': true)
+
+#tips.card.text-white.bg-info.mt-2 role="tab" style="display: block;"
+  .card-header.py-2
+    i.fa.fa-lightbulb
+    = t('exercises.implement.tips.heading')
+  .card-body.text-dark.bg-white.p-2
+    = render(partial: 'tips/collapsed_card', collection: @tips, as: :exercise_tip)