PostgreSQL 12 RC1 Press Release Draft

Hi,

Attached is a draft for the PostgreSQL 12 RC1 press release. Please let
me know if you find any errors or notable omissions.

I'd also like to take this opportunity as a chance to say thank you to
everyone for your hard work to get PostgreSQL 12 to this point. I'm
personally very excited for what should be yet another fantastic release
that will provide a lot of great features and enhancements for our users!

Thanks,

Jonathan