cbindgen panics when the config file is missing #411
Description
We can easily replace the unwrap with a better error message, happy to write a patch if this would be a useful addition.
Example:
$ rm cbindge.toml
$ cbindgen --config cbindgen.toml --crate inc --output inc.h
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 2, kind: NotFound, message: "No such file or directory" }', src/libcore/result.rs:1165:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace.