Testing/pytest: Harmonise/reduce testable data

[epogrebnyak]

tests have too many (3 sets) of testable data created at different times with different intent, need to harmonise them:

• conftest.py - formerly 'hardcoded.py'
• test_mwe.py - something for the least possible end-to-end test
• test_common_specification.py - has newer version of conftest.py/hardcoded.py or part of it

I prefer two latest datasets, but conftest.py may also have useful stuff.

Testable data is sorted by following categories (can be seen in test_mwe.py):

• raw data + as files
• spec/cfg + as files
• imported raw data
• labelled_rows
• stream of flat data
• dataframes

[epogrebnyak]

program diagram:

https://www.dropbox.com/s/skra419ioxfpa8h/2016-01-03%2014.51.37.jpg?dl=0

[epogrebnyak]

All constants are now present only in two in two new tests in new folder: https://github.com/epogrebnyak/rosstat-kep-data/tree/master/kep/test/pytest/new

No other fixtures/constants are needed for end-to-end tests.