Post Cassini 1.0.0 maintenance (Part 2)

Prior to creation of nanbield branches:

• Update Kas config to track upstream master
• Update LAYERSERIES_COMPAT
• Update image names in CI and documentation
• Add meta-secure-core for Arm platforms
• In CI only, enable debug-tweaks for firmware so recovery image can be used to flash distro
• Update to kas 4.0

Known Issue:

• ptest-runner v2.4.2 stalls if BATS scripts run shell commands as root