Makes edit_roi_counters work with new ct/sct

Closes #1770 (closed)

This command was not anymore working cause it was relaying on SCANS. And those commands do not use anymore SCANS to store content.

This MR rework the code to check if Flint have already something to display about the detector. This approach is anyway better.

Changes:

• edit_roi_counters always open ROI editor
  • Doing nothing if Flint already displays something
  • Else with the last image from the detector, if there is one
  • At worst with a place holder
• edit_roi_counters with a count time will do a ct on detector.image (and not detector)
  • If there is buggy ROIs, cause there is no ct on the ROIs, you still can edit them
• This MR reworks few other things
  • Rework the Lima node to be able the reuse a piece of code to read image
  • Create a flint.set_static_image which can be used to set an image
    • This could be use to display normalized image computed in bliss side

Here is the result with a place holder: