HTML generator has been included in clang-tools-extra release notes.
clang-doc documentation file has been updated.
Sorry for the delayed review, but a few things I caught :)
Also, please make sure to update the the release notes/flag documentation for the patches you have in progress that add features or flags.
This should also include new flags and new features like template handling.
For this to work, you'd also need to pass the --executor=standalone flag.