Chain_err intellisense support in Intelij rust plugin

I faced again an issue with Intelij not being able to resolve chain_err from error-chain crate. As a result, all development experience is poor in the IDE.

Previously I used this workaround but it stopped working, because it seems the IDE recognizes now cfg macros.

I really hoped that support for macros parsing solves the issue for error_chain! macro natively, but it turned out it is not yet solved.

If someone is interested in solving this now, here is another workaround, which I figured out and applied in my project. Works perfectly. Once the IDE starts supporting error-chain natively, dropping the workaround would be as simple as dropping the file.

Hope it helps somebody.