rename "microbit" package to "core" #414 (#270)

* rename "microbit" package to "core" #414

* shouldn't edit the package id.

* updating package.json

* updated the wrong version

* missed updating pxt.json of tests

libs/radio/pxt.json

@@ -0,0 +1,25 @@
+{
+    "name": "radio",
+    "description": "The radio services",
+    "files": [
+        "README.md",
+        "shims.d.ts",
+        "enums.d.ts",
+        "radio.cpp",
+        "radio.ts"
+    ],
+    "public": true,
+    "dependencies": {
+        "core": "file:../core"
+    },
+    "yotta": {
+        "config": {
+            "microbit-dal": {
+                "bluetooth": {
+                    "enabled": 0
+                }
+            }
+        }
+    },
+    "installedVersion": "rlfgis"
+}