[horde] Little change for Windows Compatibility

[frank@sagurna.de]

Cause i had the Problem with slashes/backslashes i have an idea to get better Compatibility with windows based webserver.
Changing one line is the only thing needs to be done:

horde/config/registry.conf

change line 51:
    $webroot = strstr(dirname(__FILE__), '/' . array_shift($webroot));

to:
    $webroot = strstr(str_replace("\\","/",dirname(__FILE__)), '/' . array_shift($webroot));

I do not know if linux gives back backslashes in directory names?
But if not this will be a quick solution.

Regards 

Frank