#4 Show to the user that the datafile is cropped

[Alois]

Once a datafile is cropped by the use of the tool in the Axis menu, there is no further indication that the file is shown only partly.

Possible solutions:

• A line in the main panel saying this file is cropped. E.g. in the mod section.
• Move the crop tool from the frame menu to the mod area. This would be consistent
  with the internals of the cropping facility.