macro-based method for calling Ilastk h5 datasets if names are unknown a priori

[pdd2110]

Hi,

Currently, when used in macros, the Ilastik import command requires hard-coding the datasetname prior to opening. This can be a bit troublesome, especially in batch mode if datasetnames change from one image to another. Two thoughts for what would make this more user-friendly:

1. Is it possible to enable Regex-based calls here, as is available in headless mode? If there are zero or more than one result, prompt the user selection window. If only one, then open that one automatically.
2. Could you include a macro function to return a list of the h5 datasets (and/or shapes) without having to import?

I know that Ilastik already does the second whenever running the import command since it shows up in the IJ Console window. Being able to access these data beforehand would be really helpful.