fallback to genereal wifi settings if tethering settings activity cannot not be found

app/src/main/java/se/leap/bitmaskclient/fragments/TetheringDialog.java

 package se.leap.bitmaskclient.fragments;
 
 import android.app.Dialog;
+import android.content.ActivityNotFoundException;
 import android.content.ComponentName;
 import android.content.Intent;
 import android.graphics.drawable.Drawable;
@@ -200,12 +201,18 @@ public class TetheringDialog extends AppCompatDialogFragment implements Observer
         spannable.setSpan(new ClickableSpan() {
             @Override
             public void onClick(@NonNull View widget) {
+                try {
                     final Intent intent = new Intent(Intent.ACTION_MAIN, null);
                     intent.addCategory(Intent.CATEGORY_LAUNCHER);
                     final ComponentName cn = new ComponentName("com.android.settings", "com.android.settings.TetherSettings");
                     intent.setComponent(cn);
                     intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                     startActivity(intent);
+                } catch (ActivityNotFoundException e) {
+                    Intent intent = new Intent(Settings.ACTION_WIRELESS_SETTINGS);
+                    startActivity(intent);
+                }
+
             }
         }, startIndex, endIndex, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);