doxygen tag-files are missing function-like keywords (e.g. static_assert)

[cmorty]

This is probably the same as #78, but I'm not sure.

The tag-files seem to be missing multiple entries. I'm specifically looking at static_assert. It shows up in link-map.xml yet not in any of the .tag files. I tried adding it to index-functions-cpp.xml, yet that has no effect.

[PeterFeicht]

static_assert is a keyword, does the tag file contain other keywords? What did you add to index-functions-cpp.xml that didn't work?

What other entries are you missing, can you give a list? If it's C++20 stuff, I just did a PR adding a bunch of new things and a couple old ones.

[cmorty]

@PeterFeicht Ok, PBKAC: Yes, all the keywords are missing. Would be nice having the function-style keywords like static_assert , the casts, alignof, etc. in the list, though. As for the other missing functions, those were a PBKAC, too. Sorry for the noise.

[PeterFeicht]

I suppose we could add those as functions, I'll see if that works.