runc: split Pipe, Io, and PipedIo to async and sync modules

[Mossaka]

An attempt to resolve #326 (comment)

Questions: should we add cargo build -p runc to the CI since the CI is not building runc with default target at all?

Can you take a look at this PR? @ningmingxiao, @mxpv

[jokemanfire]

I think this change is great ,but how about using pipe but not using fifo directly, because there's so many problem which I meet in FIFO direct. #278

[Mossaka]

My goal is to do a refactoring so that the code can compile. I am happy to rebase on your Pr if that works

[jokemanfire]

My goal is to do a refactoring so that the code can compile. I am happy to rebase on your Pr if that works

I think I should wait for your split , because I forget the sync feature too, that pipe problem is only existing in async feature.