[Xmonad] take 6?: darcs patch: SshConfig.hs: support global known hosts file, unique host list

Trying as attachment this time. Really need to hammer on the client config on university machines... :/ -- brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH