Improved 'interpret every make.py' user experience.

Example:

    Red Example Score (2013) - segments

       1: segment 01
       2: segment 02
       3: segment 03

          segments - copy (cp)
          segments - new (new)
          segments - remove (rm)
          segments - rename (ren)

    > mpyi*
    Will interpret ...
      INPUT: /Users/trevorbaca/Documents/abjad/scoremanager/scores/red_example_score/segments/segment_01/__make__.py
     OUTPUT: /Users/trevorbaca/Documents/abjad/scoremanager/scores/red_example_score/segments/segment_01/output.ly
     OUTPUT: /Users/trevorbaca/Documents/abjad/scoremanager/scores/red_example_score/segments/segment_01/output.pdf
      INPUT: /Users/trevorbaca/Documents/abjad/scoremanager/scores/red_example_score/segments/segment_02/__make__.py
     OUTPUT: /Users/trevorbaca/Documents/abjad/scoremanager/scores/red_example_score/segments/segment_02/output.ly
     OUTPUT: /Users/trevorbaca/Documents/abjad/scoremanager/scores/red_example_score/segments/segment_02/output.pdf
      INPUT: /Users/trevorbaca/Documents/abjad/scoremanager/scores/red_example_score/segments/segment_03/__make__.py
     OUTPUT: /Users/trevorbaca/Documents/abjad/scoremanager/scores/red_example_score/segments/segment_03/output.ly
     OUTPUT: /Users/trevorbaca/Documents/abjad/scoremanager/scores/red_example_score/segments/segment_03/output.pdf
    Ok? y

    >