Add a license.txt file

[jernst]

Is it GPLv2 like some of your other code?

[scripting]

MIT license. https://github.com/scripting/river5/blob/master/river5.js

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On Sunday, July 16, 2017, Johannes Ernst ***@***.***> wrote: Is it GPLv2 like some of your other code? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#18>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABm9O0uYc3271x34IqGlgHQ4dwrAVAtLks5sOnFjgaJpZM4OZZ2-> .

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[jernst]

Ah, thanks.

[scripting]

I also added a LICENSE file.