db/fields:
db/fields:

Added NullFloatField type.


Former-commit-id: 3a54ca25e6755cde7f8b61743b438141e6716a3f [formerly d99d1061c8a898dcbbfdf4a5fcfc6fb36d497b79]
Former-commit-id: 40f7f9ea174d8295afbb2e97a781c6e9ef3bd5d6
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine