gui: bump theme version to 4

updates to reboot page (change to listbox)

Change-Id: I02331693ca9a407e0bd30c633f2b799ece7b3636
diff --git a/gui/theme/landscape_mdpi/ui.xml b/gui/theme/landscape_mdpi/ui.xml
index 24458ec..3a41262 100755
--- a/gui/theme/landscape_mdpi/ui.xml
+++ b/gui/theme/landscape_mdpi/ui.xml
@@ -6,7 +6,7 @@
 		<title>Backup Naowz</title>
 		<description>Default basic theme</description>
 		<preview>preview.png</preview>
-		<themeversion>3</themeversion>
+		<themeversion>4</themeversion>
 	</details>
 
 	<include>