[horde] Linux shadow file support

[Sean Coleman]

Hello,

After looking through the various posts in the development threads, I 
noticed
that some work had been proposed to authenticate horde to Linux shadow file
using md5 but reviewing the current code, it appears this has yet to be 
done. Is
there a philosophical reason to not support linux shadow format and md5 
passwords or has no one
simply done the work to add this capability. I ask because I am 
interested in pursuing
this fix but don't want to do something which is not needed.

Thank you,

Sean Coleman