redoing old macro

went back to preprocessing macro for tracking:

// K_SpaceEqualizer2.ijm
// attenuate the edynamic range of the image for contrast enhancing.
// started for enhancing virus+microtubule sequences.
//Kota Miura (miura@embl.de)
//050517,
//070301 modified and resavved as v2
// use algorithm2. ititially, background ROI must be defined.