For us, it practically only changes the fact that `A<A<int>>` is now
used instead of the C++03 compatible `A<A<int> >`.
Note: clang-format 10+ changed the `Standard` arguments to fully
specified `c++11`, `c++14`, etc. versions, but we can't use `c++17`
now if we want to preserve compatibility with clang-format 8 and 9.
`Cpp11` is still supported as deprecated alias for `Latest`.
Remove now unnecessary bindings of signal callbacks in the public API.
There might be some false positives that need rebinding if they were
meant to be public.
No regular expressions were harmed in the making of this commit.
(Nah, just kidding.)