[14.0] group_backend: new module and rename group_backend to base_group_backend

As a developer we have to keep in mind using this module and grant a user with 's group is
equivalent to grant 's group everywhere  has been used.

Co-authored-by: Jean-Charles Drubay <jcdrubay@users.noreply.github.com>

base_group_backend/__manifest__.py

@@ -0,0 +1,23 @@
+# Copyright 2021 Pierre Verkest <pierreverkest84@gmail.com>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+{
+    "name": "Group backend",
+    "version": "16.0.1.0.0",
+    "category": "Tools",
+    "author": "Pierre Verkest, Odoo Community Association (OCA)",
+    "license": "LGPL-3",
+    "maintainers": ["oca"],
+    "website": "https://github.com/OCA/server-backend",
+    "depends": ["base", "mail"],
+    "demo": [
+        "demo/test-model.xml",
+        "demo/ir.model.access.csv",
+        "demo/backend_dummy_model.xml",
+    ],
+    "data": [
+        "data/res-groups.xml",
+        "security/ir.model.access.csv",
+    ],
+    "installable": True,
+    "application": True
+}