Fix: https://github.com/Eyescale/Equalizer/issues/275

Do not execute dump Image tests if not GPUs available.
Merge pull request #276 from julitopower/master

Fix: https://github.com/Eyescale/Equalizer/issues/275
Merge branch 'master' of https://github.com/Eyescale/Equalizer
-Use boost program_options instead of tclap for command line parsing
-Removed tclap dependency entirely, now building on windows again
Merge branch 'removeTCLAP' of https://github.com/VMML/Equalizer
CR #278