Revert "MB-8020 Change compacted file layout"

This reverts commit c18c5b2a71ad5d60897bbdff6b90c4c2e7a0382e.

Conflicts:
	src/db_compact.c

Change-Id: Ifa7daefd61738cc285b8c9dbadb3bd3c66e054fb
Reviewed-on: http://review.couchbase.org/26681
Reviewed-by: Fulu Li <fulu@couchbase.com>
Reviewed-by: Filipe David Borba Manana <fdmanana@gmail.com>
Tested-by: Aaron Miller <apage43@ninjawhale.com>