spacemanager: Fix property annotations

The property annotation of DefaultAccessLatencyForSpaceReservation is
missing the default value. The patch also addresses the problem that
spacemanager.default-access-latency was not defined in terms of the
property it is deprecating.

Target: trunk
Require-notes: no
Require-book: no
Acked-by: Paul Millar <paul.millar@desy.de>
Patch: http://rb.dcache.org/r/5820/