Openfisca-core

Breaking changes

* Deprecate and remove the `fin` attribute in XML parameters.
- The end date of a parameter is assumed to be the start of the next one.
- The `<END>` indicates that a parameter does not exist anymore
* Deprecate and remove the `fuzzy` attribute in XML parameters.
- By construction, the value of a parameter is always extended towards the future.
- To indicate a likely change of the legislation, a `<PLACEHOLDER>` can be added.
* Deprecate and remove `reforms.create_item`
- New items are created directly with the method `reforms.update_items`.
* Deprecate and remove `reforms.split_item_containing_instant`
- Splitting items does not make sense in the new convention. Use `reform.update_items` to update the parameters.

Breaking changes

These breaking changes only concern variable and tax and benefit system **metadata**. They **do not** impact calculations.

* Make `tax_benefit_system.get_package_metadata()` return a `dict` instead of a `tuple`
* Make `column.source_file_path` a relative path (was absolute before)
* Make `column.url` a list instead of a string

New features

* Make `tax_benefit_system.get_package_metadata()` more robust
- Handle reforms
- Handle tax and benefit systems that are not defined within a package and/or a distribution

Technical changes

* Turn `Variable`s with a `start_date` and/or a `stop_date` into `DatedVariable`s
- This is transparent for users.

* Do not cache values for neutralized variables
- To reduce memory usage for large population simulations

* Improve the raised error message when a wrong period type is given as an input

Breaking changes

* In YAML tests:
- Deprecate and remove the `IGNORE_` prefix
- Deprecate and remove the `ignore` property
* In the YAML test runner:
- Deprecate and remove the `force` option (`-f` in the shell script)
- Deprecate and remove the `default_absolute_error_margin` option (`-M` in the shell script)
- Deprecate and remove the `default_relative_error_margin` option (`-m` in the shell script)

New features

* Add `Reform` and `numpy.round` (as `round_`) in the model API
* Introduce `tax_benefit_system.apply_reform(reform_path)`
* Allow YAML tests to declare the reforms they need to be executed (through the `reforms` property)

Technical changes

* Move the `dummy_extension` to `OpenFisca-Dummy-Country`
* Test `openfisca-run-test` script

* Rename `neutralize_column` to `neutralize_variable`
- Deprecate `neutralize_column` without removing it
* Document `neutralize_variable`