package.xml should not be part of the content list

Change-Id: I5cd3d77b2f1cf66dc9edeb4d238ccc6a51bdeb65
Reviewed-on: http://review.couchbase.org/25632
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>