prepare for PreferenceScreen support, remove some old depricated android libs

server/src/main/kotlin/eu/kanade/tachiyomi/source/ConfigurableSource.kt

@@ -1,8 +1,16 @@
 package eu.kanade.tachiyomi.source
 
-// import androidx.preference.PreferenceScreen
+/*
+ * Copyright (C) Contributors to the Suwayomi project
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+
+import androidx.preference.PreferenceScreen
 
 interface ConfigurableSource : Source {
 
-//    fun setupPreferenceScreen(screen: PreferenceScreen)
+    fun setupPreferenceScreen(screen: PreferenceScreen)
 }