Could not find NVML
Hi, 

I'm excited to try this out. Unfortunately when building on a freshly installed Xubuntu 16.04, I get the error that it cannot find NVML. I've verified that libnvidia-ml.so etc are in the cuda directory, and it's able to find Cuda after I specify where Cuda is. I tried specifying the flag it asks for (NVML_SOURCE_DIR or whatever it is -- the output is on another computer), but it doesn't seem to mean anything to Cmake. 