re-enabled database serialization in bin/db_load_src_model
re-enabled database serialization in bin/db_load_src_model


Former-commit-id: 4ebeefc650f7d24d0835086b574afd098d7f297d [formerly 2f2f28ca89c11ce0b18cd60b1a8527abf53e77be]
Former-commit-id: 273ce2ebb446342a37d2bd8eae740be0c57aa8c4
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine