When the colored output was originally added in https://github.com/wasmerio/wasmer/pull/489 and there was a discussion then about that it should ideally be in a higher-level crate rather than in the runtime-core library crate.
I agree with that, users of the library shouldn't be required to bring in the colored crate dependency and ideally also not have stdout/stderr output either, that should be controlled by the application that uses wasmer-runtime-core, not the library.
Disabling stdout/stderr output would be more intrusive but I wanted to at least not have colored output and another crate dependency so this change removes the colored output and the "colored" crate.
