add vscode launch file for run/debug easier in vscode

.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": [
+
+        {
+            "name": "Launch bbgo",
+            "type": "go",
+            "request": "launch",
+            "mode": "auto",
+            "program": "${workspaceFolder}/cmd/bbgo",
+            "cwd": "${workspaceFolder}",
+            "env": {},
+            "args": ["backtest", "--debug"],
+            "showLog": true
+        }
+    ]
+}