mythen: add roicounters
the mythen detectors, are strip detectors used like MCA, but today there is no way to create soft roicounters, the scientists last week complained about this missing features.
Please, use the same API as for other MCA for the roicounters.
It could be great at the end to unify the roicounters API for 1D and 2D detectors, that get the users a bit lost to have 2 differents API.
Edited by Laurent Claustre