Sphinx-generated documentation sketch including source-code docs generating

I recreated sphinx docs structure, and changed Makefile a little bit so each action re-generates source_code rst docs.
Also sphinx uses lots of submodules to let user decide on format of output documentation (ePub, etc...)
Source-code generating itself requires sphinx-apidoc

Also python functions' docstrings itself are not in reST format

def sum(number1, number2):
   '''
   :param number1: integer - first number
   :param number2: integer - second number
   :rtype: integer
   '''