account journal lock date

This module is inspired by the OCA account_journal_lock_date 11.0 module. Differences compared to the OCA 13.O account_journal_lock_date module:

• Single Lock Date field. By default a Lock Date on a journal will lock operations for all users, including the Financial Advisor (can be relaxed via an inherited module).
• The Lock Date will be checked when posting the Journal Entries, hence not while creating draft invoices.