update models
models update: Giant Component
properly update checksum for Giant Component
default nightly.sh to not cleaning

having the default destroy stuff is too error-prone.
to explicitly request cleaning, pass --clean
Merge remote-tracking branch 'origin/5.0.x'
Merge remote-tracking branch 'origin/master' into core
Merge remote-tracking branch 'origin/core' into headless

Conflicts:
	test/checksums.txt
fix regression where checksum commands weren't working

forgot to update this before during headless package reorg