stage1: fix root top-level-struct typename

- during diagnostics the string representation for root was empty
  and now is `(root)`
- retrofitted all other namespace-qualified type naming to elide
  prefixing with root

closes #2032
42f2814d9aMichael Dusan committed on 10/9/2019, 9:36:13 PM· committed by Andrew Kelleyparente0ab685
4 files changedLine totals unavailable