Remove unnecessary lets.
Add comments and warnings to __get_type instantiation.
Refactor field info code out of get_type creation.
Move assignment of struct_def out of get_type.
Temporarily cast types and clone String.

This allows more asserts to succeed, allowing a quick test of the
template functionality.
Add an empty model implementation.
A template should take a Model as generic.
Fix typo.
Move code to separate modules.
Move template definition and impl to own module.

Also renames TestTemplate to StringTemplate.
Remove unused imports.
Working renderer!
Return a String as a slice, not as a String.

This removes the need to clone the string.
Update to latest rustc version.

Use enum namespacing feature to get more readable code.
Add initial sequence support.

The sequence data is not yet generated, but generating types should
work.