Fix missing returns statement.
Add flattenApplication* transform.

This transformation flattens trees of applications using CArgs
information. This bypasses the need to use std::bind, but relies on the
assumption that the application of a CArgs function will get all of its
arguments at the same time.
Remove automatic attachment of template specializations.

We rely sufficiently on template parameter deduction that we no longer
need to explicitly specialize most function calls.
Generate application expressions based on flattened trees.
Generate CArgs 1 annotations where possible.
Attach CArgs annotations for Seq.