[FIX] PEP8 length to 80 as required by OCA
[IMP] activate flake8 check in travis file
[ADD] Add account_journal_period_close_module
[DOC] account_journal_period_close: improve module description
fix newline at eof
[ADD] module account_balance_line
replace osv.Model by orm.Model
remove noqa

[FIX] PEP8 and add noqa directive in Scenario while waiting improvement on quality tools