Hi, I was looking into citext support for persistent recently, and noticed that postgresql-simple had FromField instances for CI ST.Text and CI LT.Text, but not matching ToField instances. Is there any reason for this, and if not would you like me to add those two instances?

I also saw that citext wasn't in the generated src/Database/PostgreSQL/Simple/TypeInfo/Static.hs file. Would you like me to add it there by modifying tools/GenTypeInfo.hs?

I already have everything working without making any changes to postgresql-simple, I just thought this might be a welcome contribution so thought I'd ask.

Possibly related? #130