- Add SPDX headers
- Indent consistently (tabs, not a mix of 2-space, 4-space, and tabs)
The scripts were originally added without a license header.
Since they are simple, and re-usable, and not particularly
interesting, I've made the license explicitly 2-clause BSD.
This is unlike the rest of Calamares, which is GPLv3+; the
build system and support scripts are not the software itself.
dec30d70fd