Implemented AreaSource.get_bounding_box [demos]
Implemented AreaSource.get_bounding_box [demos]


Former-commit-id: 7d3620ce0b8364c0a086a99649e4c877ea3d3013
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine