docs on native flags

docs/markdown/location/options.md

@@ -0,0 +1,19 @@
+# Options
+
+For the `backup` and `forget` commands you can pass any native flags to `restic`.
+
+```yaml
+locations:
+  foo:
+    path: ...
+    to: ...
+    options:
+      backup:
+        tag:
+          - foo
+          - bar
+```
+
+In this example, whenever `autorestic` runs `restic backup` it will append a `--tag abc --tag` to the native command.
+
+> :ToCPrevNext