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* Transform BillingInfo create and update view into one BillingInfoCreateOrUpdateView. This will require implementors to change these views if they were overriden. Also if one of the `billing_info_create.html` or `billing_info_update.html` templates has been overriden, he has to transform the code into the new `billing_info_create_or_update.html` template.
* Celery dependency was removed. Now the implementor has to connect the `plans.tasks.autorenew_account` `plans.tasks.expire_account` tasks by himself or use management command.
* Disable particular e-mails from system through configuration: `PLANS_SEND_EMAILS_NO_SEND_TYPES`, `PLANS_SEND_EMAILS_PLAN_CHANGED`, `PLANS_SEND_EMAILS_PLAN_EXTENDED`
* If e-mail template with `.html` appendix, send HTML e-mail.
* Add basic recurring payments support
* Added `expire_accounts` management command as an alternative to Celery task
* Added free plan support, fix expired quotas.
* It is now ensured, that we have only one default migration.
* Use parameters to compose error messages in validators.
* Fix problem with changed `AUTH_USER_MODEL` and user link in `PlanAdmin`.
* Determine country by IP address in billing info, if geolite2 is installed
* Added possibility to define `PLANS_VALIDATORS` as lazy imported string.
* Supporting Django 2.1
* The range when the plan was extended is now stored in `Order.plan_extended_from` and `Order.plan_extended_until`.
* The fron/until extension range is shown to the user during order confirmation
* UserPlans are now automatically created with initial migration or with `create_userplans` adminaction.
* Added possibility to define `PLANS_APP_VERBOSE_NAME` to personalize plans' `verbose_name`
* Return back to order after setting up billing info