make new fixtures in csv2df tests

[epogrebnyak]

This review is similar to #38.

[epogrebnyak]

48c4125 sets new file structure in src/kep2 and reduces dependencies. everything is run by runner.py + main section has own examples in each module.

Naming reference is mailman and BW style guide. Used from it: __all__, tentative 1 class per module.

Major TODO is restoring tests, but should be easier once the components are decoupled. After restoring tests will rename kep2 to kep.

[epogrebnyak]

New file structure testing: (structure was changed. Ignore this comment)

• emitter.py
• helpers.py
• label.py
• parcer.py
• reader.py
• runner.py
• specification.py
• util_row_splitter.py
• validator.py

[epogrebnyak]

TODO:

• check all csv2df/*.py modules have __all__ property.
• check methods/classes in __all__ are tested
• make new fixtures
• prepare follow-up questions (xfail vs skip, ... )

[bakakaldsas]

__all__ property in modules:

• emitter.py
• parser.py
• reader.py
• runner.py
• specification.py - added empty needs to be filled
• util_label.py
• util_row_splitter.py - added empty needs to be filled
• validator.py - added empty needs to be filled

[bakakaldsas]

Tests by module:

• emitter.py:
  • Emitter
• parser.py
  • extract_tables
• reader.py
  • Reader (skip)
  • open_csv
• runner.py
  • get_dataframes
  • Vintage (skip)
  • Collection (skip)
• specification.py
  #TODO __all__
• util_label.py
  • make_label
  • split_label
  • extract_varname
  • extract_unit
• util_row_splitter.py
  • (tested with doctest)
• validator.py
  #TODO __all__