Add fscan
This MR adds the support of fscan types of scan.
It is needed mostly for integrator, but also for supporting ID15A and ID11 tomography formats.
This MR also adds tomoscan.test.utils.tomoscan_utilstest (based on silx ExternalResources
) because the existing class UtilsTest
relies heavily on data compression ('archive_XX' keyword in almost all methods).