Updating babel & other dependencies to fix audit issues

Author: tvillaren

Diff for: .babelrc

@@ -1,10 +1,31 @@
 {
-    "presets": ["env", "stage-2"],
+    "presets": [
+        ["@babel/preset-env", {
+            "useBuiltIns": "entry",
+            "corejs": "3"
+        }]
+    ],
     "env": {
         "test": {
-            "plugins": ["istanbul"]
+            "plugins": ["istanbul",
+                ["@babel/plugin-proposal-decorators", {
+                    "legacy": true
+                }],
+                "@babel/plugin-proposal-function-sent",
+                "@babel/plugin-proposal-export-namespace-from",
+                "@babel/plugin-proposal-numeric-separator",
+                "@babel/plugin-proposal-throw-expressions",
+                ["@babel/plugin-proposal-class-properties", {
+                    "loose": true
+                }],
+                ["@babel/plugin-transform-runtime",
+                    {
+                        "regenerator": true
+                    }
+                ]
+            ]
         }
     },
     "retainLines": true,
     "sourceMaps": true
-}
+}