Support for tag/variable async lamdas?

[jcfontecha]

I was looking at this PR where support for async functions was introduced. I wonder if there are any plans to support variable (or tag) async functions? Functions that we can call with the {{function}} syntax that take no parameters (Func<Task<string>> or Func<dynamic, Task<string>>)

Any plans to support this or any workarounds for this? Thanks!