feat: add custom types for annotations

Feature

Summary

This MR provides an implementation of the newly introduced Body Object in the AnnotationAPI which replaces the simple string body. This change adds a custom type, x-content-type, to the AnnotationAPI which allows for distinguishing the different types of annotations without parsing their value.

Compliance to “Definition of Done”

• Unit tests passed
• Code reviewed
• Product Owner accepts the User Story

Documentation

• I provided my functions with appropriate documentation
• I updated existing documentation

Tests

Are we able to test this new feature?

• Yes, everything can be done via unit tests.
• Yes, you can test by following these steps:
  • build the database locally
  • go to ${IP}/exist/restxq/annotations/ahikar/syriac/sample_edition/annotationPage.json

Changelog

• I added a statement to the CHANGELOG.

Version number

• I bumped the version number in build.properties.

Closes

Closes #112 (closed)

Logs and Screenshots

/cc Mathias Göbel, Frank Schneider, Michelle Weidling