Podlite 1.12: a build for Android 4.1 (Xperia J) with ExoPlayer, speed and skip silences

- One build per Android level, as in Tenda and Plexamp Lite: build/Podlite.apk (Android 2.2+, versionCode 1308) and
  build/Podlite-api16.apk (Android 4.1+, 1316), from shared src/ plus platform/api8 or platform/api16; build.sh now
  runs on the local toolchain (aapt2, dx or R8, signapk.py; the JKS key converted for the run).
- Android 4.1 build: ExoPlayer 2.18.7 behind an Engine interface, with playback speed (player header) and skipping
  silences (Settings), a 3-minute buffer and MediaPlayer as fallback for audio it can't decode; a notification and
  lock screen with the cover and buttons; Holo; a menu button on phones without a Menu key; metered networks for
  "download on Wi-Fi only".
- Both builds: tlskit's Http.abort fix (a finished response's pooled connection is no longer closed under a later
  request); the lock screen's and newer headsets' play/pause keys.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

res/layout/activity_home.xml

@@ -33,6 +33,13 @@
             android:layout_height="fill_parent"
             android:background="@drawable/row_sel"
             android:src="@drawable/ic_refresh" />
+
+        <ImageButton
+            android:id="@+id/menu"
+            android:layout_width="@dimen/header_h"
+            android:layout_height="fill_parent"
+            android:background="@drawable/row_sel"
+            android:visibility="gone" />
     </LinearLayout>
 
     <LinearLayout