Added time measurement for the ARMv7 port

app/system/CMakeLists.txt

app/system/test_dispatch_full.cc

app/system/test_dispatch_full.oil

app/system/test_dispatch_only.cc

app/system/test_dispatch_only.oil

app/system/test_dispatch_switch.cc

app/system/test_dispatch_switch.oil

app/system/test_dispatch_termination.cc

app/system/test_dispatch_termination.oil

arch/armv7/dispatch.cc

arch/armv7/dispatch.h

arch/armv7/machine.h

arch/armv7/nvic.h

arch/armv7/platforms/xmc4500/machine_impl.cc

arch/armv7/platforms/xmc4500/nvic_impl.cc

arch/armv7/settings.h

arch/armv7/startup.cc

arch/armv7/syscall.h

arch/armv7/timer.cc

arch/armv7/timer.h