upgrading to yui 3.9.0
updating history notes
no longer forcing arrow to use a specific yui version, relying on the default one shipped with arrow which is 3.6.0 at the moment.
Merge pull request #1035 from caridy/yui-390

upgrading to yui 3.9.0
restoring custom arrow config
Merge pull request #1037 from caridy/yui-390

restoring custom arrow config, this should fix jenkins, hopefully!