Expose speaker meta as columns in the list table

[DrewAPicture]

It would be helpful if we could expose the Gravatar email and WP.org username meta in columns on the Speakers list table in the back-end. This would primarily help when you're moving information back and forth between the budget sheets and the site to be able to easily grok what's filled and what's missing.

[DrewAPicture]

Happy to spin up an environment and create a patch if all is agreeable.

[iandunn]

I think that's a good idea :)

​The Meta Environment will automatically provision a local copy of WordCamp.org for you, and plugs into an existing VVV install if you have one :)

[iandunn]

In 2199:

WordCamp Post Type: Add Gravatar and W.org Username columns to Speakers screen.

Fixes #1023
Props SergeyBiryukov