1) add a new poincare plot parameter named: timing (boolean, default -
False), 
  used to add a column with value of a moment time when a sliding window
is generated,
  every value of the first item in previous data window is added up;
  if a previous data window starts like the current window a mean value
of a previous window is used instead
2) correct passing of parameter named movie_clean_frames during creation
of a poincare movie
3) in function:
hra_core.movie_utils.__generate_multiprocessing_movie__(...)
use 'find' command instead of 'ls' because of its limitation concerning
the number of files that can be included in a listing,
this is the case for frames of a 24-hour recording