Redesign splashpage program section & split out partials

app/views/conferences/_highlights.haml

@@ -0,0 +1,18 @@
+.row
+  .col-md-12
+    %h3.text-center
+      Program Highlights
+.row
+  .col-md-12
+    .row.row-centered
+      - @conference.highlighted_events.each do |event|
+        - speaker = event.speakers_ordered.first
+        .col-md-3.col-sm-3.col-centered.col-top.highlights
+          = link_to conference_program_proposal_path(@conference.short_title, event),
+            class: 'thumbnail' do
+            = image_tag speaker.gravatar_url(size: 300),
+              class: ['img-responsive', 'img-circle'],
+              title: speaker.name
+            .caption
+              %h3.text-center= speaker.name
+              %h4.text-center= event.title