DDS — Ref-20 Semantics_of_factory_delete_methods

The specification does not state what happens if the application tries
to use an entity after it has been deleted by means of the
corresponding "delete" operation on the factory. This is specially
relevant in languages such as Java (or C++ when using the "var" types)
that automatically maintain reference counts. Is the deletion delayed
until the last reference is release?

**PROPOSAL**

Modify section 2.1.1.1 and ad the return code
ALREADY_DELETED. Similarly add the "const ReturnCode_t RETCODE_
ALREADY_DELETED = 9" to the IDL in section 2.2.3

State that it is an error for the application to use an entity after
it has been deleted. Also state that, in general the result is
unspecified and may depend on the implementation or the PSM. Also
state that in the cases where the implementation can detect this, the
operation that uses the deleted entity should return RETCODE_
ALREADY_DELETED (e.g. calling DataWriter::write on a data writer that
has been deleted).

see below