ProfileService: Add a listener to start it on boot

This will allow automatically starting profiles on boot.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

app/src/main/java/com/wireguard/android/BootCompletedReceiver.java

@@ -0,0 +1,14 @@
+package com.wireguard.android;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+
+public class BootCompletedReceiver extends BroadcastReceiver {
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        Intent startServiceIntent = new Intent(context, ProfileService.class);
+        context.startService(startServiceIntent);
+    }
+}