Relicense to `MIT OR Apache-2.0 OR Zlib`

[lunabunn]

As per the discussion in #112, I am initiating the process to relicense this project to the MIT OR Apache-2.0 OR Zlib triple license.

Rationale for Licensing

Currently fontdue is licensed solely under MIT. In addition to not being as compatible as it could be with the rest of the ecosystem, most of which uses the MIT OR Apache-2.0 dual license, MIT is also problematic in that in lacks a patent protection clause and an explicit contribution clause. In fact, Rust itself is only keeping around MIT as a licensing option (instead of using just Apache-2.0) for GPLv2 compat.

If this project were to be dual-licensed under Apache-2.0 and MIT, contributors would be providing the Apache-2.0 patent grant, even though the project will still remain usable with the MIT license. It will also be more compatible with the rest of the ecosystem. Adding a third Zlib licensing option then grants the additional flexibility of not needing to include attribution or license information in product distributions that do not include source code.

This permissive, flexible, and compatible licensing would be ideal for a crate such as fontdue that is most likely to be used indirectly as dependencies of other crates in its users' dependency graphs.

Contributor checkoff

Being a change in license, this requires all contributors who have made copyrightable changes to the fontdue repository to agree.

For simplicity (and because IANAL), given below is a list of all contributors to the fontdue project. If you agree to relicensing, please comment verbatim:

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

If you have any concerns, please leave those in this issue thread as well so that they can be discussed.

• [x] @mooman219
• [x] @robmcl4
• [x] @weswigham
• [x] @twitchyliquid64
• [x] @Brooooooklyn
• [x] @ryan-scott-dev
• [x] @cedric-h
• [x] @MarimeGui
• [x] @maroider
• [x] @Some-Dood
• [x] @bschwind
• [x] @tronical
• [x] @Riey
• [x] @deeprobin
• [ ] @deprilula28
• [ ] @avl
• [x] @avafloww

[maroider]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[Riey]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[bschwind]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[weswigham]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[deeprobin]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[BastiDood]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

Thanks for the heads up, by the way!

[tronical]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[avafloww]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[twitchyliquid64]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

:partying_face:

[robmcl4]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[ryan-scott-dev]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[MarimeGui]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[Brooooooklyn]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[cedric-h]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to chose any one at their option.

[avl]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to choose any one at their option.

[avl]

(I'm sorry for being so late to answer. I think I was notified when I was pinged when this PR was opened, but I didn't read enough to realize I was being asked to take action. Sorry about that! Good initiative!)

[deprilula28]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to choose any one at their option.

[grovesNL]

I license past and future contributions under the triple MIT OR Apache-2.0 OR Zlib license, allowing licensees to choose any one at their option.

[mooman219]

Thanks everyone!