[Paraview] paraview crashes during startup

[Burlen Loring]

A fresh clone as of midday yesterday PV client fails to launch with the 
below error. I enabled mpi and python, everything else is default value.

libGL error: No matching fbConfigs or visuals found
libGL error: failed to load driver: swrast
X Error: BadValue (integer parameter out of range for operation) 2
   Extension:    153 (Uknown extension)
   Minor opcode: 3 (Unknown request)
   Resource id:  0x0

apparently ParaView's attempting to load swrast,  a mesa renderer, 
although I have nvidia gpu and drivers. I also tried the OpenGL2 backend 
and encountered the same error. To work around this I manually located 
the nvidia headers and opengl library and forced cmake to use those.

I'm not sure if you want to call this a bug in ParaView or the CMake 
find opengl module. But ParaView should probably correctly detect and 
use nvidia drivers, and ignore mesa drivers, which are likely present on 
every system no matter if third party gpu/driver is installed or not.

Burlen