reorg files

--HG--
rename : tests/settings/test_settings.py => tests/vi/test_settings.py
simplify if statement
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rename methods
add tests for state.py
extract method
add tests for state.py
extract method
sort imports a-z
add tests for state.py
extract method; minor changes
minor changes
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edit changelog
Added tag 0.8.9 for changeset f1d678a18f69
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change tests
change method name
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