Fail to install 0.5.0

[David Sferruzza]

Hi!

When I try to install dummyhttp 0.5.0 using cargo, I get the following error:

error: The default runtime flavor is `multi_thread`, but the `rt-multi-thread` feature is disabled.
   --> /home/user/.cargo/registry/src/github.com-1ecc6299db9ec823/dummyhttp-0.5.0/src/main.rs:219:1
    |
219 | #[tokio::main]
    | ^^^^^^^^^^^^^^
    |
    = note: this error originates in the attribute macro `tokio::main` (in Nightly builds, run with -Z macro-backtrace for more info)

error: could not compile `dummyhttp` due to previous error
error: failed to compile `dummyhttp v0.5.0`, intermediate artifacts can be found at `/tmp/cargo-installuu9WOk`

This feels like you need to enable additional features to your tokio dependency, right?