DDS — Ref-162 Separate_transient_into_two_kinds

The description of the DURABILITY Qos in section 2.1.3 is ambiguous
with regards to the TRANSIENT kind. It would appear that there are in
fact two kinds:

The first interpretation "TRANSIENT_LOCAL" would have the durability
tied to the liveliness of the DataWriter..

The second interpretation "TRANSIENT_GLOBAL would tie the durability
to the fact that some "durability servide" in the system is still
executing.

It should be explained which of these interpretations is meant.

**PROPOSAL**

Modify the QoS table in 2.1.3 to separate the TRANSIENT durability
into two kinds: TRANSIENT_LOCAL and TRANSIENT.

TRANSIENT_LOCAL ties the durability to the liveliness of the
writer. This is the mandatory level described in Appendix A.

TRANSIENT allows the durability to survive the liveliness of the
DataWriter. Explain this kinds in the table and in section 2.1.3.2

see below