I am assuming that ignoring them was unintentional. If they are ignored, some tools, like cargo, will consider the files inexistent, even if they're comitted, for the purpose of publishing. This leads to the build failing in such cases.

For the same reason as the previous two files.

* Add exceptions for files mentioned by @slaren

I did leave .clang-tidy since it was explicitly ignored before.

* Add comments for organization
* Sort some lines for pretty
* Test with `make` and `cmake` builds to ensure no build artifacts might be comitted

Per comment by @ggerganov