Adds notes to Superset plugin generator about TypeScript errors the u…

…ser is likely to encounter.

superset-frontend/packages/generator-superset/generators/plugin-chart/templates/README.erb

@@ -22,6 +22,31 @@ To add the package to Superset, go to the `superset-frontend` subdirectory in yo
 npm i -S ../../<%= packageName %>
 ```
 
+If your Superset plugin exists in the `superset-frontend` directory and you wish to resolve TypeScript errors about `@superset-ui/core` not being resolved correctly, add the following to your `tsconfig.json` file:
+
+```
+"references": [
+  {
+    "path": "../../packages/superset-ui-chart-controls"
+  },
+  {
+    "path": "../../packages/superset-ui-core"
+  }
+]
+```
+
+You may also wish to add the following to the `include` array in `tsconfig.json` to make Superset types available to your plugin:
+
+```
+"../../types/**/*"
+```
+
+Finally, if you wish to ensure your plugin `tsconfig.json` is aligned with the root Superset project, you may add the following to your `tsconfig.json` file:
+
+```
+"extends": "../../tsconfig.json",
+```
+
 After this edit the `superset-frontend/src/visualizations/presets/MainPreset.js` and make the following changes:
 
 ```js