Cycles / CUDA:
* Remove support for  CUDA Toolkit 4.x, only Toolkit 5.0 and above are supported now.
* Remove support for sm_1x cards (< Fermi) for good. We didn't officially support those cards for a few releases already, now remove some special code that was still there. 

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk@60613 954f8c5b-7b00-dc11-b283-0030488c597c