Update templates for Yarn compatibility

templates/ReactReduxSpa/template_gitignore

@@ -35,6 +35,7 @@ Obj/
 !/wwwroot/dist/_placeholder.txt
 !/ClientApp/dist/_placeholder.txt
 
+/yarn.lock
 
 # MSTest test Results
 [Tt]est[Rr]esult*/

templates/ReactReduxSpa/tsconfig.json

@@ -1,5 +1,6 @@
 {
   "compilerOptions": {
+    "baseUrl": ".",
     "moduleResolution": "node",
     "target": "es6",
     "jsx": "preserve",
@@ -7,7 +8,11 @@
     "sourceMap": true,
     "skipDefaultLibCheck": true,
     "lib": ["es6", "dom"],
-    "types": [ "webpack-env", "whatwg-fetch" ]
+    "types": [ "webpack-env", "whatwg-fetch" ],
+    "paths": {
+      // Fixes "Duplicate identifier 'Redux'" error when packages were installed via Yarn (by specifying which .d.ts file is authoritative)
+      "redux": ["./node_modules/@types/redux/index"]
+    }
   },
   "exclude": [
       "bin",