feat: re-add licenses by SPDX identifier, mark shorthand aliases as deprecated

[edward-ly]

Resolves #1274.

Adds the SPDX identifiers for the currently supported licenses as valid enum values for the <licence> tag. Automatically converts apache, mit, and mpl to Apache-2.0, MIT, and MPL-2.0, respectively, when importing or creating a new app release. agpl and gpl3 are left alone for now as they are implicitly assumed to map to AGPL-3.0 and GPL-3.0, but those identifiers are also deprecated themselves.

Feel free to correct me if I'm wrong, but that was my interpretation based on the discussion so far.

Tasks for the app store admin (who I believe is @Altahrim?) after merging:

• rebuild app store documentation
• add the following rows to the Licenses table:

id	name
AGPL-3.0-only	GNU Affero General Public License v3.0 only
AGPL-3.0-or-later	GNU Affero General Public License v3.0 or later
Apache-2.0	Apache License 2.0
GPL-3.0-only	GNU General Public License v3.0 only
GPL-3.0-or-later	GNU General Public License v3.0 or later
MIT	MIT License
MPL-2.0	Mozilla Public License 2.0

[AndyScherzinger]

Besides my comments this looks good to me, yet this can only be merged after the same PR has been merged on server v31.0.0, to ensure v31.0.0 (and later) won't break.

[oleksandr-nc]

Tasks for the app store admin (who I believe is @Altahrim?) after merging:

This will probably be done by me.

CI is expected to fail, it is broken due to invalid translations.

I have informed @nickvergessen about this situation, for now I will temporarily remove the translations from the repository (but they will be returned by the bot again soon)

Edited: CI should be fixed now, thanks to Joas!
nextcloud/docker-ci#702

[edward-ly]

Andy's suggestions have now been applied. By the way, with the new license IDs, I've been thinking maybe we need to change the way the license is displayed in the server as well (e.g. here), but I'll leave it up to you whether anything needs to be done about it or not.

[AndyScherzinger]

I've been thinking maybe we need to change the way the license is displayed in the server as well (e.g. here), but I'll leave it up to you whether anything needs to be done about it or not

I had a similar thought if we should just drop the "-licensed" in the rendering

[oleksandr-nc]

looks good to me

[AndyScherzinger]

👍

[provokateurin]

Btw can someone script PRs to update the license identifiers of all apps built by the company? If they were built after the OC split then we can safely assume that AGPL-3.0-or-later is meant. Alternatively if no direct change is possible due to ambiguity it would be nice to open an issue in each repo to warn about this.