We already have a LICENSE file that covers the Zig Standard Library. We
no longer need to remind everyone that the license is MIT in every single
file.
Previously this was introduced to clarify the situation for a fork of
Zig that made Zig's LICENSE file harder to find, and replaced it with
their own license that required annual payments to their company.
However that fork now appears to be dead. So there is no need to
reinforce the copyright notice in every single file.
These were never working with native CPU features. In this branch,
we fix native CPU features not being enabled on Windows, and regress
f128 language features. In the llvm10 branch, all this is fixed,
and the tests are re-enabled.
