[RMV] - Remove empty file
[IMP] - Update no_update cron after migration
[IMP] - move contract template recurrence info to line level
[FIX] - Fix contract line model description
[IMP] - Link contracts to analytic accounts
[FIX] - Fix pylint
[IMP] - Move chatter and attachments from analytic account to contract
[IMP] - Move account_analytic_id to contract line level
[IMP] - Improve version check in migration script
[IMP] - Move contracts followers from analytic accounts
[ADD] - Add mail.activity.mixin to contract.contract model
remove data drop from migration scripts
[12.0][FIX] - Fix _init_last_date_invoiced
fix flake8
[ADD] - Update contributors list