1) add a module, hra_core.movie_utils,  for utils functionality
concerning generation of a movie file,
the following functionality is added
def __generate_movie__(movie_specification)
    function generate a movie using mencoder based on frame's files
extension  or a file listing

def generate_movie(movie_name, movie_dir,   movie_width, movie_height,
movie_fps, movie_frames='*.png')
    function used by client code to generate a movie according to
specified parameters; at this time multiprocessing
    version is used only for Linux OS

def generate_multiprocessing_movie(movie_name, movie_dir,  movie_width,
movie_height,  movie_fps, movie_frames='*.png')
    generating a movie with given specification using multiprocessing;
all frames are divided into excluded sets of files, for each set
    a movie is create, in the next step all parts are joined to create
one final movie

2) add a module, hra_core.system_utils.execute_command, which contains
some functionality concerning environment of operating system,
   the following functionality as added:
def execute_command(command, lines_of_output=0)
    execute command, returns outcome (in one a string object) depending
on
    value of lines_of_output parameter:
    0 - no outcome
    -1 - all outcome
    <number> - number of lines of outcome

def run_command(command)
    execute command, returns iterator over all outcomes

3) use generate_movie function in client code:
hra_math.time_domain.poincare_plot.poincare_plot_movie_maker.PoincarePlotMovieMaker.save_movie(self)