Vendor dependencies for 0.3.0 release

vendor/thiserror-impl/src/lib.rs

@@ -0,0 +1,40 @@
+#![allow(
+    clippy::blocks_in_conditions,
+    clippy::cast_lossless,
+    clippy::cast_possible_truncation,
+    clippy::enum_glob_use,
+    clippy::manual_find,
+    clippy::manual_let_else,
+    clippy::manual_map,
+    clippy::map_unwrap_or,
+    clippy::module_name_repetitions,
+    clippy::needless_pass_by_value,
+    clippy::range_plus_one,
+    clippy::single_match_else,
+    clippy::struct_field_names,
+    clippy::too_many_lines,
+    clippy::wrong_self_convention
+)]
+#![allow(unknown_lints, mismatched_lifetime_syntaxes)]
+
+extern crate proc_macro;
+
+mod ast;
+mod attr;
+mod expand;
+mod fallback;
+mod fmt;
+mod generics;
+mod prop;
+mod scan_expr;
+mod unraw;
+mod valid;
+
+use proc_macro::TokenStream;
+use syn::{parse_macro_input, DeriveInput};
+
+#[proc_macro_derive(Error, attributes(backtrace, error, from, source))]
+pub fn derive_error(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as DeriveInput);
+    expand::derive(&input).into()
+}