Better diagnostics for compile error in template

Currently when there's a syntax error in a template, there is a message to the console like:

```
DEBUG: TODO handle this compilation error better: { stack: [Getter/Setter],
  arguments: [ '{' ],
  type: 'unexpected_token',
  message: [Getter/Setter] }
```

Need to check out how the error should be best communicated to the user and remove this message.
