Added vscode syntax highlighting under /tools

tools/toylang.vscode-highlighting/.vscode/launch.json

@@ -0,0 +1,17 @@
+// A launch configuration that launches the extension inside a new window
+// 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": [
+        {
+            "name": "Extension",
+            "type": "extensionHost",
+            "request": "launch",
+            "args": [
+                "--extensionDevelopmentPath=${workspaceFolder}"
+            ]
+        }
+    ]
+}