chore: Clean up unused files, imports, and work on getting end-to-end tests and unit tests running (#2272)

extensions/cornerstone/package.json

@@ -41,15 +41,12 @@
     "prop-types": "^15.6.2",
     "react": "^16.11.0",
     "react-dom": "^16.11.0",
-    "react-redux": "^6.0.0",
-    "react-resize-detector": "^3.4.0",
-    "redux": "^4.0.1"
+    "react-resize-detector": "^3.4.0"
   },
   "dependencies": {
     "@babel/runtime": "7.7.6",
-    "classnames": "^2.2.6",
     "lodash.merge": "^4.6.2",
-    "lodash.throttle": "^4.1.1",
+    "lodash.debounce": "4.0.8",
     "react-cornerstone-viewport": "4.0.2"
   }
 }