Support toggling hotspots in app

This is a just-for-fun feature. It probably doesn't work.

mobile/src/main/java/be/mygod/vpnhotspot/App.kt

@@ -5,6 +5,7 @@ import android.app.Application
 import android.content.Context
 import android.content.SharedPreferences
 import android.content.res.Configuration
+import android.net.ConnectivityManager
 import android.os.Build
 import android.os.Handler
 import android.preference.PreferenceManager
@@ -37,6 +38,7 @@ class App : Application() {
     lateinit var deviceContext: Context
     val handler = Handler()
     val pref: SharedPreferences by lazy { PreferenceManager.getDefaultSharedPreferences(deviceContext) }
+    val connectivity by lazy { getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager }
 
     fun toast(@StringRes resId: Int) = handler.post { Toast.makeText(this, resId, Toast.LENGTH_SHORT).show() }
 }