CHANGES IN VERSION 1.3.8
------------------------

NEW FEATURES

    o transform utils
    o adding label/scale utils

Bug fixing

    o fix warning
    o fix bugs in circular view 


CHANGES IN VERSION 1.1.16
------------------------

NEW FEATURES

    o addSteping add extra arugments group.selfish to control stepping method

    o add estimateCoverage method for fast estimate coverage

SIGNIFICANT USER-LEVEL CHANGES

    o addStepings rename to addStepping
