r3461

OPTIMIZATION: remove 15 interfaces from the codebase:

   DotsInterface
   DynamicLineSpannerInterface
   DynamicTextInterface
   DynamicTextSpannerInterface
   NonMusicalPaperColumnInterface
   NoteColumnInterface
   RehearsalMarkInterface
   ScriptInterface
   SpanBarInterface
   StemInterface
   StemTremoloInterface
   SystemStartBarInterface
   TrillPitchAccidentalInterface
   VerticalAlignmentInterface
   VerticalAxisGroupInterface

RESULTS:

   timer = timeit.Timer('Note("c'4")', 'from __main__ import Note')
   print timer.timeit(1000)
   5.13 sec (r3461)
   3.98 sec (r3461 with opt)
   # 22.4 % speed increase

   note = Note("c'4")
   timer = timeit.Timer('note.format', 'from __main__ import note')
   print timer.timeit(1000)
   2.60 sec (r3461)
   2.03 sec (r3461 with opt)
   # 22.0 % speed increase

   iotools.profile_expr('Note("c'4")')
   2797 function calls (2778 primitive calls) in 0.008 CPU seconds (r3461)
   2170 function calls (2151 primitive calls) in 0.006 CPU seconds (r3461 with opt)
   # 22.4 % fewer function calls

   iotools.profile_expr('note.format')
   2053 function calls (1636 primitive calls) in 0.004 CPU seconds (r3461)
   1633 function calls (1336 primitive calls) in 0.004 CPU seconds (r3461 with opt)
   # 20.5 % fewer function calls

   notes = [Note("c'4") for x in range(1000)]
   Partition of a set of 664003 objects. Total size = 74904504 bytes. (r3461)
   Partition of a set of 535003 objects. Total size = 61220504 bytes. (r3461 with opt)
   # 18.3 % less memory
