Nzshm-model

Fixed

- correlations use list comparison rather than cast to set to avoid unhashable type TypeError

Added

- rupture_set_id to branch

Changed

- renamed `nshm_1.0.0` to `nshm_v1.0.0`
- renamed `nshm_1.0.4` to `nshm_v1.0.4`

Added

- new NSHM_1.0.4 model
- correlations between fault systems

Changed

- flattened logic trees using combinations of fault system logic tree branches
- renamed field on SourceLogicTree `fault_system_branches` to `fault_system_lts`
- ensure logic tree classes are JSON serialisable

Changed

- refactored project structure for packaging
- scripts moved to /scripts package
- changelog format for bump2version
- remove docs build

Added

- poetry with: pytest, coverage, tox, flake8, mypy, black, isort, bump2version
- github actions for CI/CD
- source_logic_tree feature

Initial release of the NZ NSHM 2022 revision