FS#10783 - WPS translation

- Use the %Sx skin tag in WPS to translate 'Next Track', 'Next', and 'of' (X of Y tracks)
- New conditional skin token 'Sr' which checks whether the currently loaded language is an RTL language (Hebrew/Arabic). It uses lang_is_rtl().
- Added Hebrew translation


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@23638 a1c6a512-1295-4272-9138-f99709370657

wps/cabbiev2.128x96x2.wps

@@ -20,6 +20,6 @@
 %s%ac%?it<%it|%fn>
 %s%ac%?ia<%ia|%?d2<%d2|(root)>>
 %s%ac%?id<%id|%?d1<%d1|(root)>>
-%sNext: %ac%It
+%s%Sx|Next:| %ac%It
 
-%al %pc%ac%pp of %pe%ar%pr 
+%al %pc%ac%?Sr<%pe %Sx|of| %pp|%pp %Sx|of| %pe>%ar%pr