swc_atoms:
- add some atoms
swc_ecma_ast:
- ast nodes for typescript
- `ClassMethod` -> `Method`, `ClassMethodKind` -> `MethodKind`
- private class method / class property
- use separate type for tagged template literals
- add `declare` field to `Decl`s
- make function body optional
swc_ecma_parser:
- rename Type to TokenContext
- support decorators
Note: error reporting for invalid decorator is not implemented yet
- merge `Config` into `Syntax`
- Use DiagnosticBuilder for error type
This is to make backtracking cheaper.
swc_ecma_transforms:
- add `strip` pass
