Encapsulate nimble code into NimbleController.

Handle all GAP events.

src/Components/Ble/NimbleController.h

@@ -0,0 +1,19 @@
+#pragma once
+
+#include <cstdint>
+#include <host/ble_gap.h>
+
+namespace Pinetime {
+  namespace Controllers {
+
+    class NimbleController {
+      public:
+        void Init();
+        void StartAdvertising();
+        int OnGAPEvent(ble_gap_event *event);
+      private:
+        static constexpr char* deviceName = "Pinetime-JF";
+        uint8_t addrType;
+    };
+  }
+}