feat: allow to use one application for multiple repositories (#111)

* allow to use one application for multiple repositories

* update tests

* handle None append argument everywhere

* rewrite repository definition logic

* drop optional flags from docs

* support of new schema in systemd units

* add migration docs and ability to migrate tree automatically

* use repostory id instead

* verbose multiarchitectureerror

* object path support for s3 sync

* fix tests after rebase

docs/ahriman.models.rst

@@ -164,6 +164,14 @@ ahriman.models.report\_settings module
    :no-undoc-members:
    :show-inheritance:
 
+ahriman.models.repository\_id module
+------------------------------------
+
+.. automodule:: ahriman.models.repository_id
+   :members:
+   :no-undoc-members:
+   :show-inheritance:
+
 ahriman.models.repository\_paths module
 ---------------------------------------