[Feature] db_commit plugin allows a more verbose commit

prints logf messages to the screen buffer and dumps the
output to .rockbox/db_commit_log.txt

logs warnings about tags that can't
be displayed by the current font

adds an option to the tagcache using the file
.rockbox/database_commit.ignore to prevent auto commit

Change-Id: Ib381b3b6d9dd19d76c95d0e87e605f7378e29674

apps/plugin.c

@@ -832,7 +832,7 @@ static const struct plugin_api rockbox_api = {
 
     /* new stuff at the end, sort into place next time
        the API gets incompatible */
-
+    tagcache_commit_finalize,
 };
 
 static int plugin_buffer_handle;