Add AFL license

[faissaloo]

Pull Request description

This repository is without a license, this is a problem since it technically means no one is able to do anything with it and opens people up to the possibility of legal action against them or the project. This project is already partly licensed under the AFL, having inherited it from other code and as such I think it's the most appropriate license.

Note however that the chkesr code is provided under the vague "FreeMCBoot license", TnA has informed me that this refers to the GPL as this is what FreeMCBoot was distributed under before 1.7 not the FreeMCBoot license used today but I haven't been able to find a version of FreeMCBoot old enough to verify this. If this is the case the entire project will have to be placed under the GPL which would be problematic because the AFL is incompatible with the GPL.

I realise this seems like a small issue but I think it's important.

[AKuHAK]

I am not pretty sure which license should it be. Yes, some parts of the code use AFL (ps2sdk related), but it is only related to the external part of the code. Maybe another @ps2homebrew can help with this. There were so many maintainers over time. Who can be responsible for license changing? Current maintainers even if they change only ~5% of the code? Older maintainers which are unreachable for a long time?

[faissaloo]

In terms of licensing changes you would have to in theory get the consent of every person who authored code that still present in the repository, which is a large task.
What you can do however is find all files where the vast majority of code has been written by someone who is still reachable and have them agree to provide it under a given license and place licenses on just those files until eventually all source code has been accounted for.
For people who are completely unreachable or who don't want to license their code, their code would need to be replaced.

This is in effect a similar situation to a change of license so I'd have a look at this: https://softwareengineering.stackexchange.com/questions/55326/can-you-change-a-license-once-you-pick-one

[uyjulian]

If someone complains, we can simply undo this. So I'm going to merge this for now