Task Runner
Maycoon provides a task runner architecture to spawn asynchronous tasks in the background.
You are required to specify a task runner during compile time (using the feature array in your Cargo.toml).
By default, the tokio-runner feature is enabled, which uses the tokio runtime.
There's also a dummy-runner feature which will panic on any method call, but can be used to compile maycoon without
specifying a task runner (e.g. if you want to create a library).