* Vendor import unsafe_target_features as curve25519-dalek-derive
Co-authored-by: Jan Bujak <jan@parity.io>
* Remove feature gates from avx2/ifma
* Add buildtime compile diagnostics about backend selection
* Add build script tests
* Documentation changes
* Disable simd related features unless simd was determined via build
* Add note and test about the override warning when unsuccesful
* Reduce complexity in build gating via compile_error
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Co-authored-by: Jan Bujak <jan@parity.io>
Co-authored-by: Michael Rosenberg <michael@mrosenberg.pub>