Changes to plotf and ifs functions in ifs.py
Changes to plotf and ifs functions in ifs.py

List of changes:
-- ifs function now returns xy coordinates and does not plot fractal anymore
-- remove title and color parameters from ifs function
   (as they are no more needed there)
-- switch around color and title parameters in plotf function
-- add default values to color and title parameters in plotf function
   (they are the same as previously in ifs)
-- rename title parameter to win_title in plotf function
   (to be more descriptive)
-- introduce a few more pyplot options into plotf function
-- update all docstrings and dependent functions

f171a9a3497c8b/fractals