Lifecycle section: Incorporate review feedback from security group

[mlagally]

See: w3c/wot-security#169

[mlagally]

Arch call on 3.9.:
The Information lifecycle needs to be discussed with PING based on first draft text.
This should be ideally run by the security TF before.

[mmccool]

Issue w3c/wot-security#169 has been closed as the review has been completed, but we expect further work to take place here to incorporate the suggestions into the Architecture document before this issue can be closed. The above link to the closed wot-security issue is still relevant as it has the results of the review.

[mlagally]

Suggest to close and create a new issue when we receive new feedback from ping.