Added a custom form field for PickleFied
Added a custom form field for PickleFied

For better handling of PickleField types in forms.


Former-commit-id: 65a59da99e0a203a0f33bf9369febda5399e9503 [formerly 65a59da99e0a203a0f33bf9369febda5399e9503 [formerly 8adec3736ef0c868cc6c1f54ab66c4b7f6c9fb5e]]
Former-commit-id: 10f81b9d215cb1571cb66b169c0026aa437f3691
Former-commit-id: 1f1136a1741057edadb1de3d539c8e4b462c01e2
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine