Add Clang-Format style file

[leha-bot]

We MUST use the "STL-naming" scheme , and we SHOULD use the code style like Linux kernel (it's discussible ☺️ )

*The key words MUST and SHOULD in this issue are to be interpreted as described in [RFC2119] 😋

[shiz01]

Maybe it make sense to look at the file clang-format in llvm stl:
https://github.com/llvm/llvm-project/blob/main/libcxx/.clang-format

It might look like this:
master...feature/clang-format_llvm_libcxx

Fine? Or will we write our own?