A grace period for getting rid of JSON license jars

The recent moving of the JSON license to category X means that a number of projects cannot do any
releases until this is fixed.  I know this includes Hadoop, Hive, and Spark, and probably a number
of others since hadoop-common (which many project use) depends on jars from json.org.  The Hive
team in particular is trying to get a maintenance release out which is blocked by this.

I talked with Jim Jagielski briefly today and he suggested that perhaps we could have a grandfather
clause on this so that projects that already are using it could continue to, at least for a period
of time, so that they can continue to produce releases rather than needing to spend unplanned time
switching out this library[1].

To be specific I propose we give projects already using this license 6 months to clean this up in
which they can continue to release with dependencies on the JSON license.

Alan.

1. The amount of time to fix this will not be trivial.  Based on a little bit of digging I’ve
done the alternatives are not 100% identical in their behavior which will mean projects will need
to thoroughly test the replacements and change their code to deal with the differences.