Run all dhall-lang tests for normalization
Update to new UnionType selection semantics
Fix rubocop except for parser metrics
fix type => [value|element]_type
Refactor LetBlock, allow single LetIn
Clean up style violations
Remove multi-argument applications
They only exist in binary encoding, so let's keep them there.
Make every Expression a ValueSemantics and use the known list of
attributes to map generically over any AST node.
Introduces a conditional, but removes boilerplate from every single
Internal flag to disable for acceptance tests from the standard (which
assume beta-only normalization in some cases). Otherwise, just always
alpha normalize as we go.
Bare minimum refactor to pass the metrics
Pass most compliance tests
No import or multiline string support yet
Beta normalization complete
Implement "shift" function for variable indices
All beta normalization except for functions