BLE HF2 log service (#1549)

* basic hf2 service

* service to send hf2 log messages

* use common console.log

* updated shims

* adding config

* adding simulator

* fix hf2 logging

* hide console blocks

libs/bluetooth/pxt.json

@@ -6,7 +6,9 @@
         "enums.d.ts",
         "shims.d.ts",
         "bluetooth.ts",
-        "bluetooth.cpp"
+        "bluetooth.cpp",
+        "BLEHF2Service.h",
+        "BLEHF2Service.cpp"
     ],
     "icon": "./static/packages/bluetooth/icon.png",
     "public": true,