Waldur-core

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- Introduced Executor layer for a single point of backend logic.
- Added migration script for moving iaas VMs to openstack module.
- Reworked price estimates to keep historical resource values and metadata.
- Exposed available resource actions through REST.
- Fixed quota duplication error.
- Dropped emitting of events about structure unit changes.
- Added tags filtering to resource views.
- Dropped Killbill dependency for OpenStack price estimates.
- Bugfixes.

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- Extracted Jira support app to plugin.
- Added synchronization during service settings recovery.
- Added admin command for shared service settings SPLs and services recreation.
- Added support for creating custom events by staff users.
- Implement generic quota aggregation.
- Add a management command for DRF API generation.
- Bugfixes.

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- Added additional quota types.
- Allow deletion of resources from ERRED state - for cleanup flows.

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- Added service setting quotas.
- Added new style aggregator quotas.
- Display connected projects and service of service settings.
- Bugfixes.

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- Extracted Oracle app to plugin.
- Moved SPLs and settings synchronization tasks to separate queue.
- Added documentation about the structure module.
- Refactored /admin for price estimates.
- Moved SPL synchronisation to a separate queue.
- Added quotas for service settings.
- Added CVS utils.
- NB! Fixed an issue with potential cleanup of floating IPs from all OpenStack tenants.
- Bugfixes.

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- Updated documentation for resource lifecycle events.
- Improved /admin interface, exposed installed plugins and versions.
- Made state rendering in /projects consistent.
- Fixed recovery command for service project links.
- Exposed subscription to Kill Bill and offline resources from admin page.
- Reimplemented resources summary view.
- Moved external_ips field to VirtualMachineMixin.
- Added model to resource viewset for permissions.
- Added ability to expose location with coordinates to VMs and resources.
- Added url field to /api/resources.
- Exposed OpenStack instance resize feature.
- Added a generic access_url field for Resource model.
- Added filter for default price list item in admin page.
- Refactored OpenStack Сelery tasks.
- Removed temporarily validation of TLS.
- Removed dev only app from test_settings.
- Extended DefaultPriceListItem with metadata.
- Fixed documentation typos.