Squad

* frontend:
* rewrite build settings with Django forms/views
* Standardize "settings" tab to be similar to Group and Project settings tab name
* extract "test results summary" into a shared template
* mark strings for translation
* Show "Projects" tab only if user had specific permission
* compare_projects.jinja2: add pagination to test results
* cache downloaded static assets
* frontend/project_settingspy: add more attributes
* squad/controllers/charts.js: display tooltip on line hover
* frontend: allow empty searches in test comparison page
* i18n
* Document translation process
* scripts/update-translation-files: drop empty line at the end of .pot files
* add Polish translation for SQUAD UI
* core: mark strings for translation
* core/notification.py: add number of skipped tests to default email template subject
* core/notification.py: include metrics in context of email notifications
* ci: testfetch: add option to fetch in the background
* api
* api: add subscribe/unsubscribe endpoints to Project
* api/rest: Add KnonwIssue filtering to Test object
* doc: added description for subscribe/unsubscribe endpoints
* doc/index.rst: add missing dependency on Debain/Ubuntu
* fix yaml.load default Loader warning

* api:
* Fix api/data call date arguments
* avoid crash on delayed reports with empty error message
* fix serialization of `Project.enabled_plugins_list`
* ci:
* lava: compose boot test identifier from `job_name`, i.e. instead of just
"boot", the boot tests results from lava will be named
"boot-${device-type}"
* core:
* add 'users' management command
* group membership is now represented explicitly, and there are three access levels:
* result submitters (can submit test results)
* admins (can change anything in the project)
* drop obsolete Token model
* Add support for archiving projects (Archived projects are hidden by default
from from the group page)
* docker: reduce image size
* frontend:
* Add build settings tab
* Add group and project self service interfaces. it is now possible for
regular users to:
- Create new groups (authenticated users only)
- Create users namespaces (groups in the format "~${username}"), to host
personal projects
- On groups where one is an admin:
- Edit group setttings
- Delete the group
- Create new projects
- On projects where one is a admin:
- Edit project settings
- Delete the project
* mark strings that compose the home page as translatable
* i18n: add initial infrastructure
* mail: add bulk mail headers to outgoing mail to avoid autoreplied

This release has no functional changes. It just fixes the artifacts published
for the previous release.

* core:
* models.EmailTemplate: add jinja2 syntax validation
* TestComparison: avoid loading too many objects at once.
This fixes a long-running issue with excess RAM usage on workers.
* allow superuser access to all groups, as well as access to empty groups by
group members.
* Refactor project status rebuild command
* frontend:
* add pagination to builds view
* support groups and project with empty name
* prevent displaying 'secrets' from LAVA job definition
* make regressions and fixes popover stay on screen until explicitly closed,
so the data in them can be copied for pasting elsewhere.
* docker
* docker-compose.yaml: add initial version
* celery:
* set maximum number of producer connection attempts
* api:
* Add query result limit to api/data

* Add management command to update project statues from scratch.
* travis:
* fix detection of Javascript test failures
* fix capture of exit status
* Fix a few javascripting
* config.js: removed 'content-type' configuration
* Add import to appConfig for compare.js
* Fix broken charts tests
* Refactor ng apps
* squad/_threshold_table.jinja2: restrict admin controls
* squad/_threshold_table.jinja2: give more specific restriction
* Make all ajax requests contain CSRF header
* Refactor angular apps
* Initialize charts with default summary on all environments.
* Error output missing from failed test cases in tests view.
* api: add missing fields to ProjectStatusSerializer
* core/notification.py: turn off escaping for text emails
* docs: add step-by-step on how to set up SQUAD with LAVA
* Fix previous build ordering in project status test comparison.

* Make notification strategy a per-recipient choice.
* api:
* fix URL generated to baseline in DelayedReport
* fix report caching
* add 'subject' to reports
* frontend: turn Thresholds metrics name into a select control.