Added configuration for running core tests.

Author: MIchaelMainer

.gitignore

@@ -1,4 +1,5 @@
-.vscode/
+/.vscode/*
+!/.vscode/launch.json
 .DS_Store
 .tmp
 tmp

.vscode/launch.json

@@ -0,0 +1,20 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "node",
+            "request": "launch",
+            "name": "Run core tests",
+            "program": "${workspaceRoot}/node_modules/mocha/bin/_mocha",
+            "args": [
+                "${workspaceRoot}/lib/spec/core/*.js"
+            ],
+            "cwd": "${workspaceRoot}",
+            "outFiles": [],
+            "internalConsoleOptions": "openOnSessionStart"
+        }
+    ]
+}

README.md

@@ -287,7 +287,7 @@ These steps are not required to use this library.
 
 ```npm pack``` bundles the npm module.
 
-```npm test``` runs tests of the core library (URL parsing, mock responses, etc)
+```npm test``` runs tests of the core library (URL parsing, mock responses, etc). You can also set breakpoints and run this from within Visual Studio Code by selecting the *Run core test* configuration from the Debug view.
 
 ```npm run test:types``` to run tests against the Graph API for users, groups, Excel, OneNote, etc.