helpers aren't resolved when variables are defined in the same template

[jonschlinkert]

I'm not sure if this is a bug with async-helpers, but it seems to be.

Example:

{% var foo = "bar" %}
{%= console.log(foo) %}

logs out an async id for foo.

Maybe we can expose the helper ids and related objects on the context, along with a convenience method for resolving a value from an id... not sure how or if this would work, but just wanted to throw it out there.

[tunnckoCore]

I've just done a complete refactor of this package (in 90 lines ;d) and seems to not have such bug. Supports helpers to be regular async functions and callbacks.

I'll PR to discuss there.

Btw, @doowb that idea is genius. I always was thinking how the heck this can be implemented and finally i got the idea. You just wrap the functions and return the id, then in "resolve" we loop over the ids and replace them from the given string.