add and use cgiurl_abs_samescheme
* emailauth: Fix cookie problem when user is on https and the cgiurl
uses http, by making the emailed login link use https.
* passwordauth: Use https for emailed password reset link when user
is on https.
Not entirely happy with this approach, but I don't currently see a
better one.
I have not verified that the passwordauth change fixes any problem,
other than the user getting a http link when they were using https.
The emailauth problem is verified fixed by this commit.
This commit was sponsored by Michael Magin.