get over obsolescences

[amateja]

This PR is aimed to get over obsolescences in this project and its dependencies with a few dependencies fixes.

1. pep8 project was renamed to pycodestyle (see Please rename this tool PyCQA/pycodestyle#466)
2. pyflakes has dropped python 3.3 support in version 2.0.0 (see Drop support for EOL Python <2.7 and 3.2-3.3 PyCQA/pyflakes#322)
3. missing PyYAML dependency included in setup.py script
4. unused textwrap import removed
5. global import pattern with try/catch clause replaced with python agnostic single local import
6. missing empty lines added to satisfy PEP8 guidelines (see https://www.python.org/dev/peps/pep-0008/?#blank-lines)
7. nose does not need to be present in order for the setup.py script to run (https://setuptools.readthedocs.io/en/latest/setuptools.html#new-and-changed-setup-keywords)
8. makefile targets were updated but backward compatibility is maintained
9. unsupported rstcloth.cloth.Cloth.print_block and rstcloth.cloth.Cloth.write_block methods and unused rstcloth.table.fill function were removed
10. unsupported block and block_order parameters were removed