document api endpoints (#11958)

* DEV: Documented several group endpoints

* documented some more endpoints

* document more api endpoints

* Document backup endpoints

* remove puts

spec/requests/api/schemas/json/backups_create_request.json

@@ -0,0 +1,11 @@
+{
+  "additionalProperties": false,
+  "properties": {
+    "with_uploads": {
+      "type": "boolean"
+    }
+  },
+  "required": [
+    "with_uploads"
+  ]
+}