[pywannier @ Arch-1:ak@ixion.net--2003-diplomarbeit%pywannier--prototype--1.0--patch-40]

implemented polak-ribi`ere
  involved making k-dependent matrices an actual
    vector-space-like datatype (i.e. +,-,*)
  this functionality is abstracted out into a 
    tDictionaryOfArithmeticTypes in fempy.tools.
implemented separate view in band stack visualization
implemented interactive stopping