sort out the license details

[JeffGarland]

The license text is a mess here and should really just be a single line at the top of the file. It also doesn't match the license.txt file here, which they should.

We may need help here, but ideally we'd just move this 100% to the LLVM with apache exception and move on.

[JeffGarland]

@inbal2l do you have thoughts on this? I think @camio already got permission from the original authors to use the implementation -- which as an aside had at least one significant bug :)

[wusatosi]

I am sure @camio has already ironed out the permission from the original author. I have brought this up before.
We can remove the license after @camio confirms.

[wusatosi]

We can open #76 and merge once we have confirmation.

[camio]

I can confirm.