New: initial functionality

rustfmt.toml

@@ -0,0 +1,10 @@
+edition = "2021"
+fn_call_width = 80
+format_code_in_doc_comments = true
+format_macro_matchers = true
+group_imports = "StdExternalCrate"
+imports_granularity = "Module"
+reorder_impl_items = true
+unstable_features = true
+use_field_init_shorthand = true
+version = "Two"