DSS2 — Resign Federation Execution

This service description does not explain or even mention the mechanism
according to which the RTI is expected to try to find an owner for unowned
instance attributes that become unowned as the result of invocation of the
Resign Federation Execution service with directive 1, 4, or 5 (all of which
involve ownership management). Text needs to be added that explains this
mechanism, which should work as follows:

If a federate invokes this service with either directive 1, 4, or 5, then for
each instance attribute that becomes unowned as a result, then if no joined
federates are in either the “Acquiring” or “Willing to Acquire” state with
respect to the specified instance attribute, the RTI shall try to identify
other joined federates that are willing to own the instance attribute. If any
joined federate is in either the “Acquiring” or “Willing to Acquire” state with
respect to the specified instance attribute, the RTI may try to identify other
joined federates that are willing to own the instance attribute. The mechanism
that the RTI shall use to try to identify other joined federates that are
willing to own the instance attribute is invocation of the Request Attribute
Ownership Assumption † service at all joined federates that are both eligible
to own the instance attribute and not in either the “Acquiring” or “Willing to
Acquire” state with respect to the specified instance attribute.

Add the suggested text.