Calling HALSIM_PauseTiming pauses the FPGA clock and notifiers.
Calling HALSIM_ResumeTiming resumes the FPGA clock and notifiers.
Calling HALSIM_StepTiming steps the FPGA clock and runs applicable notifiers.
This will effectively pause TimedRobot and any other notifier-based events,
but of course will not pause user threads that do not use the notifier (e.g.
image processing).
The old headers were moved into folders because doing so avoids polluting
the system include directories.
Folder names were also normalized to lowercase.
