what4 1.5.1

Only display out-of-date packages.

8 Reverse deps	Accepted versions
copilot-theorem	>=1.3 && <1.6
copilot-verifier	>=0.4
crucible	>=0.4
crucible-llvm	>=0.4.1
crucible-symio	-any
crux	>=0.4.1
crux-llvm	-any
cryptol	>=1.4 && <1.6