[horde] Garbage collection /static directory

[Arjen de Korte]

I'm not sure if this ever worked, but it looks like garbage collection  
for the /static directory when CSS and Javascript cache is place is  
not working here. Looking at

     horde/framework/Core/lib/Horde/Themes/Css/Cache/File.php
     horde/framework/Core/lib/Horde/Script/Cache/File.php

there should be a 'gc_cachecss' and 'gc_cachejs' file in the /static  
directory respectively to prevent running the GC more than once a day.  
As far as I can see, this file should be created the first time the GC  
runs. However, neither of them is present and the cached theme CSS and  
Javascript files date back many months.

I'm running Horde_Core-2.22.6. Did I miss configuring something that  
keeps Horde from GC the /static directory?