Feature/implement gis excerpt converter #153

Created by: wasabideveloper

Implementation of #153 (closed) (Closes #153 (closed) ).

• Run tests
• Tested views by hand:
  • /orders/new [get/post]
  • /orders/{orderId}
• Tested workflow by hand:
  1. Create new excerpt of HSR
  2. Choose export formats markdown, shape file and geopackage
  3. Commit extraction order
  4. Wait for conversion
  5. Download conversion results

Reviewed by:

• @das-g
• @njordan-hsr