MB-33463: Remove hexdump and replace with DiskDocKey.to_string()
MB-33463: Remove hexdump and replace with DiskDocKey.to_string()

Tidy up the logger messages to be consistent.

Change-Id: I0410661e8e7441a7b25695ef568cf7fc194bda2f
Reviewed-on: http://review.couchbase.org/110908
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Dave Rigby <a09264da4832c7ff1d3bf1608a19f4b870f93750@couchbase.com>

daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine