Fix a bad filename in HW1's compare.cpp

Was outputting HW_*
Update main.cpp

made timing information output nicer
Update main.cpp

Made timing info output nicer
Update main.cpp

Made timing output nicer.
Update main.cpp

Made timing info output nicer.
Update main.cu

Made timing info output nicer.
Update main.cpp

Made timing info output nicer.
Update CMakeLists.txt

Add debugging flags for Nvidia's NSight tools
Update CMakeLists.txt

Made nsight debugging stuff work only for debug builds - previous CMAKE if statement wasn't working appropriately (was adding flag to release builds.)