"Exotic" GNATS 4 fields

[Yngve Svendsen]

From the responses I have received, I suggest that we do as follows:

Keep the Date-Required, Release-Note and Keywords fields -- they're useful 
in their own right.
Rename Cases to Related-PRs.
Comment out Quarter in the dbconfig file, with a note to the effect that 
people upgrading from an older release-based GNATS should enable the field.

Of course, Milan has to make the final desicion on this.

- Yngve