Adding PDF Download link to the header
This changes the "Download" link into "Download PDF" and associates it with the generated PDF file.
It's fairly simplistic at the moment. In particular, we don't check to see that the PDF was actually generated for this version of this component. It is assumed to have been generated and a link is constructed based on the naming convention that we reverse engineered from Antora Assembler. I created #3 to come up with a better solution.
Edited by David Diederich