Timezone view

I brought this up a while ago, but I didn't get any responses, I assume 
due to everyone being too busy with 8.3

I think that it would be great if the pg_timezone_names and 
pg_timezone_abbrevs included a boolean field indicating if that item is 
in the Olsen DB or if it is a system alias or other added item. This 
would make it far easier to integrate the data in the view with external 
data sources that also use the Olsen DB.

It may also be beneficial to add the ISO 3166 column into that view, the 
data is in zone.tab and I can't see a reason to not include it.

- Naz.