Add rp-rs copyright notice

[thejpster]

Updates LICENSE-MIT and some source files to indicate the copyright holder.

The first commit is as required by the MIT license. The second I thought would be useful, but isn't strictly required.

[Dirbaio]

this doesn't apply to the entire repo. Would you consider the copyright line in the .rs files enough?

[thejpster]

If you give someone a copy of the software, you need to include the license text and any copyright notice (https://writing.kemitchell.com/2016/09/21/MIT-License-Line-by-Line.html)

Just including the copyright notice in the source files, along with the note that it is MIT licensed, is probably sufficient for source based releases. I don't know the details of how you manage licences in binary releases (or how/if you encourage your users to manage those licenses in their binary releases), but it would be typical to encourage distributors to take a copy of any top-level LICENSE* and NOTICE* files and to redistribute those along with the binary, and in that case, the copyright notices in the source files would be lost. Perhaps a copy of the LICENSE-MIT file at the top-level of every HAL is a reasonable compromise?

[thejpster]

I should also note that the Rust Project is Quite Bad at this currently. It's a work in progress.

[Dirbaio]

ah that's a very good point. LICENSE* files at the root seem to be the de-facto standard, copyright lines in loose .rs files won't get picked up by people writing scripts that collect *LICENSE* files like yours for their binary releases.

let's add LICENSE files to embassy-rp then.