Provide REST endpoint for document conversion

Client pushes DDI document to server with parameters source and target dialect definition name
Server responds with converted document or error message
Reuse test cases https://git.gesis.org/stardat/stardat-converter/-/blob/master/src/test/java/org/gesis/stardat/converter/StudyUnitCodebookDocumentTest.java#L87

Edited May 09, 2022 by Alexander Mühlbauer

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information