Rendering one template within another

[HCLarsen]

Liquid does have a syntax for this, but I don't see it within this library. It is a very useful part of Liquid.

https://shopify.github.io/liquid/tags/template/

[crimson-knight]

While we work toward the 100% parity with ruby liquid, we'll ensure this feature gets added. I've labeled this issue as an enhancement for now