Isolating ohif:study-list package from measurements and lesiontracker

Packages/ohif-lesiontracker/client/lib/studylist/studylistModification.js

@@ -3,6 +3,8 @@ import { Router } from 'meteor/iron:router';
 import { OHIF } from 'meteor/ohif:core';
 
 Meteor.startup(function() {
+    if (!OHIF.studylist) return;
+
     OHIF.studylist.callbacks.dblClickOnStudy = dblClickOnStudy;
     OHIF.studylist.callbacks.middleClickOnStudy = dblClickOnStudy;