This is a fairly small change; removed the statement "Pointer and
reference types in C++ code" as it does not provide any additional
knowledge that contributors are or will be aware of after further
reading into the "Pointers and References" section. It seems
unnecessary and redundant given the sentence adjacent to it.
Unfortunately we cannot enforce this with clang-format yet, as that
feature is not available. Until then, let's try to write new code
with this in mind, and convert old code as we go.
This is only meant to be about higher-level coding style, not the small
things like brace placement, indentation, etc. For all of that we just
obey clang-format.
