HTTP2 support

[siriuscor]

Some OpenID servers only support HTTP/2. I'm wondering if there is any plan to support HTTP/2, or I can also submit a pull request.

[panva]

Hello, I am not opposed. How would such support look?

[siriuscor]

I added http2 for send request, and try to keep the original workflow, also I do some test on my own ,you can view the commit at
siriuscor@d39fc17
user can add setting for http2 support
custom.setHttpOptionsDefaults({
http2: true,
});