Create offline links from samples to PDFJT documentation.
Create offline links from samples to PDFJT documentation.

- Only when generating the distribution
- This way, when PDFJT classes appear in the samples doc, users can
  click over to them, and the long package names don't appear.

datalogics-coreyy/pdf-java-toolkit-samples,datalogics/pdf-java-toolkit-samples,datalogics/pdf-java-toolkit-samples,datalogics-coreyy/pdf-java-toolkit-samples