Add more DNG 1.6 tags

[kmilos]

Add a couple of more DNG 1.6 tags since the last update from https://helpx.adobe.com/photoshop/kb/dng-specification-tags.html (seems like it's a living, not yet finalized/published spec)

[codecov]

Codecov Report

Merging #2023 (22e4baf) into main (1b53303) will not change coverage.
The diff coverage is n/a.

❗ Current head 22e4baf differs from pull request most recent head 66b1eaa. Consider uploading reports for the commit 66b1eaa to get more accurate results

@@           Coverage Diff           @@
##             main    #2023   +/-   ##
=======================================
  Coverage   61.36%   61.36%           
=======================================
  Files          96       96           
  Lines       19248    19248           
  Branches     9858     9858           
=======================================
  Hits        11811    11811           
  Misses       5101     5101           
  Partials     2336     2336           

Impacted Files	Coverage Δ
src/tags_int.cpp	77.05% <ø> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 1b53303...66b1eaa. Read the comment docs.

[piponazo]

I noticed that in tags_int.cpp there is a comment pointing to some dead resource:

   http://wwwimages.adobe.com/content/dam/Adobe/en/devnet/cinemadng/pdfs/CinemaDNG_Format_Specification_v1_1.pdf

Probably it would make sense to introduce a comment in that file with the link you shared here, so that people can access to more information about DNG tags.

[kmilos]

Do you prefer we added all the DNG related resources to the source file?

[piponazo]

LGTM. Thanks for adding the comments. It will be useful for newbies like me 🤓