Run authorizations in parallel

[foxontherock]

I had to create a certificate for 25 domains, wildcard, with dns-01 challenge.
There are 25 dns entries that had to be modified, (route 53).
But, it takes minimum 25 * 60 seconds, because they are done 1 by one.
All these DNS can be updated simultaneously, then wait for 60 seconds, and continue the process of all 25.
They can be done in parallel, to make the process run 60-120 seconds instead of 25-30 minutes.

[webprofusion-chrisc]

Thanks, yes I agree for some providers we could be doing one batch commit of DNS changes and parallel authorizations at least.