Cleanup, don't raise "RuntimeError" when a build step in Scons fails.
Cleanup, don't raise "RuntimeError" when a build step in Scons fails.

* Scons can instead just properly exit, and this will make the whole
  thing way more readable and less scary to look at.

* Of course this only affects development versions and bug encounters,
  but still.

wfxiang08/Nuitka,wfxiang08/Nuitka,wfxiang08/Nuitka,tempbottle/Nuitka,tempbottle/Nuitka,kayhayen/Nuitka,kayhayen/Nuitka,tempbottle/Nuitka,tempbottle/Nuitka,kayhayen/Nuitka,kayhayen/Nuitka,wfxiang08/Nuitka