Add support for nasm

[Jake-Shadle]

I was having issues with yasm on Windows, and noticed #752, so I just tried out nasm instead and everything seemed to work.

Resolves: #752

[briansmith]

@Jake-Shadle Are you interested in updating this based on the above feedback?

[briansmith]

Thanks for the PR and thanks for updating it in response to my previous comment. I haven't had time to test it out but I will do so if/when you rebase it.

I think we should check to see which version of nasm BoringSSL is using and use the same version.

[Jake-Shadle]

I updated the version to the one that boringssl ostensibly is using as seen https://boringssl.googlesource.com/boringssl/+/HEAD/util/bot/UPDATING#56

[briansmith]

@Jake-Shadle Thanks for the PR. I had to rewrite the CI/CD to replace Travis CI and AppVeyor with GitHub Actions. That makes your PR unmergable. I'm going to close this. I have written a new PR #1123 that attempts to accomplish the same thing yours does. I would appreciate it if you could take a look.