Remove copy of CMake module to avoid policy CMP0017
Since commit 8dd19720 (...set examples to require cmake 2.6.3 to match vtk, 2010-01-13) the entire VTK tree requires CMake 2.6.3 or higher. These versions of CMake provide the FindPackageHandleStandardArgs module so we do not need our own copy in VTK anymore. Removing this module avoids triggering new CMake 2.8.4 policy CMP0017. Therefore we do not need to set the policy at all. Revert that portion of commit 8f14f0a7 (Set CMake 2.8.4 policy CMP0017 to NEW, 2011-01-13).