Move server-side functions from viewerbase to worklist. Split multi-frame and single-image modalities into separate display sets (OHIF-36)

Packages/viewerbase/lib/helpers/studyThumbnails.js

@@ -2,8 +2,8 @@
  * A global Blaze UI helper to get the thumbnails for the given study
  */
 Template.registerHelper('studyThumbnails', study => {
-    // Creates the series stacks
-    const stacks = createStacks(study);
+    // Find the study's stacks
+    const stacks = study.displaySets;
 
     // Defines the resulting thumbnails list
     const thumbnails = [];