[FIX] account : Fixed the 'account.config.settings' object has no attribute 'start_date'.
[REM]Removed account.period object and related stuff.

[REM]Removed stuff related to account.period from every where.

[IMP]changed period_date in to date_account.

[REM]Replaced period_id with date_account from reports and imporoved stuff.

[IMP]Improved some code for account.period is now removed.

[IMP]Improved code and removed access right of journal.period