Add license and basic documentation

LICENSE:
Add GPL-3.0 license.

{{archiso,configs}/*,.editorconfig,.gitlab-ci.yml}:
Add SPDX license identifier.

Makefile:
Add SPDX license identifier.
Install the `run_archiso.sh` script as global executable `run_archiso`.
Use -D and -t flags to install to install files more generically (without a previous call to install the directory).

README.rst:
Add README outlining the project's scope, how to build images from the profiles and how to test.

AUTHORS.rst:
Add list of all direct contributors to the repository.

CONTRIBUTING.rst:
Add basic contribution guidelines, explaining the linter and the license in use.

Closes #7
Closes #3

1 files changed, 26 insertions, 0 deletions

diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
new file mode 100644
index 0000000..5073aa0
--- /dev/null
+++ b/CONTRIBUTING.rst
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+============
+Contributing
+============
+
+These are the contribution guidelines for archiso.
+All contributions fall under the terms of the GPL-3.0-or-later (see `LICENSE <LICENSE>`_).
+
+Editorconfig
+============
+
+A top-level editorconfig file is provided. Please configure your text editor to use it.
+
+Linting
+=======
+
+All ash and bash scripts are linted using shellcheck:
+
+  .. code:: bash
+
+    make check
+
+Testing
+=======
+
+Contributors are expected to test their contributions by building the releng profile and running the resulting image
+using `run_archiso <scripts/run_archiso.sh>`_.