Support tagging annotations in the structure tree

[dadza]

Description of the new Feature/Bugfix

The goal of the changes is to allow users to create PDF/UA-1 compliant documents with link annotations.

To achieve this the link annotations needed to be referenced in the document structure tree via OBJR, and create separate structure parent keys for the annotations.

Unit-Tests for the new Feature/Bugfix

The following code creates a PDF document with a link annotation that can be validated as PDF/UA-1 compliant with veraPDF:

LinkPdfUA.java

Thank you,
Lucian Chirita

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codacy-production]

Not up to standards ⛔

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