Updates to PiFM/Igor translator
Created by: rajgiriUW
Some logic and bug fixes for these translators. PiFM reorganized and slightly rewritten to match logical layout of Igor translator.
These also add two new options for ease of use in data science applications.
- adding a grp_name parameters so you can rename from the default (and usually uninformative) 'Measurement' name
- adding an append_path that lets you add the translated file to an existing *.h5 file.