This commit reflects changes to clang-format rules. Unfortunately,
these rule changes create a massive change to the codebase, which
causes an apparent rewrite of git history.
Git blame's --ignore-rev flag can be used to ignore this commit when
attempting to `git blame` some code.
* Rename Identity.hpp to identity.hpp
* Rename Identity.cpp to identity.cpp
* Rename Info.hpp to info.hpp
* Rename Intro.cpp to intro.cpp
* Rename Intro.hpp to intro.hpp
