tigefa4u projects Trac

rework-testing branch: move the `destroy_db` method from !FunctionalTestEnvironment to !EnvironmentStub, as any test might require dropping the current schema of an alternative database backend and recreating it, in case a database version difference was detected.

MultiRepos: merged 0.12dev [T8178:8199/trunk].

If running the tests using an alternate database backend which has previously been used for testing trunk, then some tests will fail due to missing 'repository' table.

The logic of the database cleanup during the tests needs to be adapted.

multirepos: Added file missing from [8202].

multirepos: Added an admin panel to manage repositories.

* `trac-admin` commands to manage repositories in the database have been moved to `DbRepositoryProvider`.
* Repository syncronization must still be triggered with `trac-admin`.

Part of #8291.

multirepos: Fixed display of repositories with errors in repository index.

multirepos: Migrated the SVN cache metadata caching to new caching infrastructure.

Related to #7723.

0.12dev: Merged [8161] from 0.11-stable, now that #G300 is fixed.

0.11-stable: Backed out [8184] due to #8282. I'll propose a better fix in #5640.

0.12dev: backout r8196 - this change triggered `LazyProxy` instances to be used in contexts where they shouldn't have been.

i18n: `Translations.load` return a `NullTranslations` instance when the catalogs are not available.

This later makes the `add` fail:
{{{
NullTranslations instance has no attribute 'add'
}}}
So better ''not'' consider the translations are active in this condition.