Added persistent single-image measurments (length, ellipse) (LT-37, LT-156)

Packages/viewerbase/lib/updateAllViewports.js

@@ -0,0 +1,6 @@
+updateAllViewports = function() {
+    var viewports = $('.imageViewerViewport').not('.empty');
+    viewports.each(function(index, element) {
+        cornerstone.updateImage(element);
+    });
+};

Packages/viewerbase/lib/viewportFunctions.js

@@ -1,5 +1,5 @@
 getActiveViewportElement = function() {
-    var viewportIndex = Session.get("activeViewport");
+    var viewportIndex = Session.get("activeViewport") || 0;
     return $('.imageViewerViewport').get(viewportIndex);
 };