examples don't track implemented code

[ijsnow]

The WIP disclaimer at the top of the REAMDE says to feel free to try out the repository but when I copy/paste the examples into my code they don't work.

It says the host macro should generate a function called invoke_handler to pass to plugin::Builder::invoke_handler but it doesn't exist.

Could you update the basic example to match the code?

[JonasKruckenberg]

Hey, so yeah the examples were outdated because for the longest time this crate broken while I was doing major refactors.
But, as of yesterday things should work again (and I'm now gearing up for another release)
so I updated the example to reflect the current state.

Also check out the examples in the examples directory for a full setup