Limiting with vsync is apparently unreliable on a number of systems;
this resulted in high CPU/GPU usage.
Also add current actual frame rate to about dialog of GUI tools.
This is enabled by the C++20 __VA_OPT__ feature.
Uses of "{}" format string were updated.
Some warning suppressions were required for older clang versions.
Also improve codegen of wpi::Logger::Log(), frc::ReportError(), and frc::MakeError();
these generate better and less redundant code if they use fmt::string_view for the
format string instead of templating on it.
Most of these were unused, the IMU ones were just debug messages.
The only one that wasn't removed is in portable-file-dialogs.cpp since
the replacement looks less trivial.
