The `extends` and `block` feature is documented [here](https://github.com/dotliquid/dotliquid/blob/93d1b9d075a069353240cae06b42c5d1506bfa7a/src/DotLiquid/Tags/Extends.cs#L12-L59). Could this be supported in Giraffe.DotLiquid? Here's a rough working version that hardcodes the templates directory: https://gist.github.com/srid/645fcc6363852e7617c4fd356463860a