* examples Makefile

  - fixed dependencies
* examples/custom.ini, examples/py2puml-custom.puml
  - using epilog for class associations
* tests/test_puml_generator.py, examples/example_globals_NS.puml
  - can be generated by simple command line
* examples/py2puml-custom.puml
  - puml_generator.deco_marker made private
* minor improvements in cli_parser
* corrected tests equality assertions
* track and test cli usage message