Consolidating and standardizing x-delete-at format

Change-Id: Idc916da1c7fe1cc43a2c26f7f7ee1d4fcdd52c89
Merge "Consolidating and standardizing x-delete-at format"
release notes and authors update for 1.12

Change-Id: I76c13957a7758287fd40dd2e9fb85277d9288977