Fix indentation from extern "C" for public headers

Files should not be indentend an entire level just because they happen
to be wrapped with extern "C". This is a leftover from the auto
formatting stuff done some time ago

Change-Id: I2a73cf9d9f37efad3f8b361a622e4a9d850ba38e
Reviewed-on: http://review.couchbase.org/36275
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Mark Nunberg <mnunberg@haskalah.org>