fixes for hotkeys usage in docusaurus

platform/core/package.json

@@ -34,7 +34,8 @@
     "cornerstone-tools": "5.1.2",
     "cornerstone-math": "0.1.9",
     "cornerstone-wado-image-loader": "^3.1.2",
-    "dicom-parser": "^1.8.3"
+    "dicom-parser": "^1.8.3",
+    "@ohif/ui": "^1.8.2"
   },
   "dependencies": {
     "@babel/runtime": "7.7.6",