Multivalued-dict

Changes:
- Adjust the position of some import statements in multivalued_dict_module.py

Changes:
- Fixed minor issues in readme.md

Changes:
- Fixed minor issues in check_self_class_call_of_meta_module.py

Changes:
- Added version number attribute.
- Changed the internal variable name of check_self_class_call_of_meta_module.py

Change from

>>> mv_d = multivalued_dict({'a': ['test-1', 'test-2', 'test-3'], 'b': 'test-4'})

>>> mv_d

multivalued_dict({'a': [['test-1', 'test-2', 'test-3']], 'b': ['test-4']})

to

>>> mv_d = multivalued_dict({'a': ['test-1', 'test-2', 'test-3'], 'b': 'test-4'})

>>> mv_d

multivalued_dict({'a': ['test-1', 'test-2', 'test-3'], 'b': ['test-4']})

Changes:
- Fixed minor issues in readme.md
- Fixed minor issues in setup.py