JCBC-623: Upgrade core-io to 1.0.1

Motivation
----------
Upgrading core-io to the latest bugfix release.

Change-Id: I042e4e0e59430e2cd9c9817d30db622136da42dd
Reviewed-on: http://review.couchbase.org/42738
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Reviewed-by: Simon Baslé <simon@couchbase.com>