MB-9893: delete and recreate corrupted access log

if attempting to open an access log whose size is less than
the minimum header size, simply delete the access log and
recreate it instead of returning ShortReadExceptions later

Change-Id: I62ed2c120341ff0ba30c2ca7d096cd76fdf6e039
Reviewed-on: http://review.couchbase.org/32868
Reviewed-by: Sundararaman Sridharan <sundar.sridharan@gmail.com>
Tested-by: Sundararaman Sridharan <sundar.sridharan@gmail.com>