During startup, a battery of tests should be run to determine OpenCL environment

[slarson]

See for example this broken stack trace: https://gist.github.com/vellamike/8d349f1fac3e52a9aff2

We should try to anticipate this kind of breakage and put a more informative warning message to the console about what is going wrong and how to fix it.

[gidili]

This is a good thought for all OpenCL based solvers (in particular real ones).