derive-termination 2.0.0

Derive the std::process::Termination trait for an enum (annotate the variants with `#[exit_code(n)`).
Documentation 
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error: Variant 'Missing' requires an #[exit_code(N)] attribute
 --> tests/ui/missing_attribute_exit_code_table.rs:7:5
  |
7 |     Missing,
  |     ^^^^^^^