Untabify file headers

Using the tab characters in there made them look like crap
when using cat in a terminal. Now they should look the same
no matter what the tab with is in your terminal.

Change-Id: I3a8df91d2874e383fdf5aba9ea3d2cf5bc861d53
Reviewed-on: http://review.couchbase.org/26105
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>