Refactor API Schema and validation

- /schema now returns full openapi/swagger schema
- That schema is used to validate incoming requests
- And used as a contract in future integration tests
- Moved route files up one level
- Fixed incorrect 404 reponses when getting objects
- Fixed saving new objects and passing jsonschemavalidation

backend/package.json

@@ -4,6 +4,7 @@
 	"description": "A beautiful interface for creating Nginx endpoints",
 	"main": "js/index.js",
 	"dependencies": {
+		"@apidevtools/json-schema-ref-parser": "^11.7.0",
 		"ajv": "^6.12.0",
 		"archiver": "^5.3.0",
 		"batchflow": "^0.4.0",