Set ServerName explicitly in TLSConfig to ensure SNI works (#145)
Set ServerName explicitly in TLSConfig to ensure SNI works (#145)

* Set ServerName explicitly in TLSConfig to ensure SNI works

Sometime since I first wrote the ACME (Let's Encrypt) code,
and today, golang needs this extra ServerName to be set explicitly
in the TLSConfig.

This is to avoid domain fronting.

https://github.com/golang/go/issues/22704

* go fmt

vulcand/oxy,mailgun/oxy