DDSSEC_ — Handle types are shared by some plugins

In §9.5.2: "All “Handle” types are local opaque handles that are only understood by the local plugin object that creates them"
should be re-phrased as:
"All “Handle” types are local opaque handles that are only understood by the local plugin objects that create or use them"

For instance: the SharedSecretHandle is created by Authentication plugin but is also used by the Cryptographic plugin to encode Tokens (§8.3.2.7). This handle can't be opaque to the Cryptographic plugin as it needs the material it contains to encode Tokens (see §9.5.2.1.2 where the un-encrypted value of the SharedSecret is required).

Correct description of Handle types on 9.5.2

Make the change suggested in the issue description