vscode minor updates

- add cmake language support to recommend extensions
 - jlink debug add stm32f427 svd
 - gitignore updates for vscode

.vscode/extensions.json

@@ -2,11 +2,12 @@
     // See http://go.microsoft.com/fwlink/?LinkId=827846
     // for the documentation about the extensions.json format
     "recommendations": [
-        "ms-vscode.cpptools",
-        "github.vscode-pull-request-github",
         "chiehyu.vscode-astyle",
+        "github.vscode-pull-request-github",
         "marus25.cortex-debug",
         "ms-python.python",
+        "ms-vscode.cpptools",
+        "twxs.cmake",
         "vector-of-bool.cmake-tools"
     ]
 }