Calendar Lite 1.5: GingerCal is now Calendar Lite, new icon and reminder icon

Renames the app (label, texts, User-Agent, PRODID, APK) and uses the new launcher icon pack
(ldpi to xhdpi, master in art/) instead of drawing one at build time. Reminders show a white
calendar glyph in the status bar (stat_notify, 18-48 px) instead of the system's colour
alarm clock, which didn't fit the Gingerbread bar. The package name, database and signing key
stay, so it installs over GingerCal and keeps its data.

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

android/org/gingercal/NetHttp.java

@@ -10,7 +10,7 @@ import java.util.concurrent.ExecutorService;
 import org.gingercal.net.CertVerifier;
 
 /**
- * Android 2.3 transport through the bundled TLS 1.2 client (org.gingercal.net, from Minamp):
+ * Android 2.3 transport through the bundled TLS 1.2 client (org.gingercal.net, from Plexamp Lite):
  * the phone's own TLS 1.0 can't reach Nextcloud, so this talks to the normal https:// address
  * directly, any method (PROPFIND/REPORT included), with keep-alive. A pinned certificate (a
  * self-signed server or an old bridge) is still honoured.