Test ocl-icd on cluster

[myurkin]

Current description of OpenCL usage is already extensive - https://github.com/adda-team/adda/wiki/OpenCL . However, for Linux the simplest options are through the packages, which are not necessarily available in the cluster environment (without root access).

In particular, currently we use standard Nvidia drivers as a source of opencl.so, which causes problems with clFFT linking (although there is a viable workaround).

So the idea is to test ocl-icd on cluster (probably, compile from source at $HOME) and update the documentation.