REUSE: Remainder of data/

- *AppImage example config*: this is old AppImage configuration,
  basically unmaintained, but copied from the **other** example
  config files which are CC0-1.0 as well.
- *Sample Linux distro*: The example Linux distro has a handful
  of trivial files, a bogus `/etc/issue`, that kind of thing.
- The bash completions are GPL-3.0-or-later
- FreeBSD packaging information is BSD-2-Clause

data/example-root/etc/issue

@@ -1 +1,4 @@
+#   SPDX-FileCopyrightText: no
+#   SPDX-License-Identifier: CC0-1.0
+#
 This is an example /etc/issue file.