Hypothesis-jsonschema

- Improved canonicalisation of conflicting `minProperties` and `maxProperties`
- Explictly reject draft-03 schemata, which are not supported
- More specific type annotations for `from_schema`
- Better performance for certain object schemata

- `enum` schema now shrink to a minimal example rather than the first value listed.
This also makes the internals more efficient in certain rare cases.
- Improved handling of bounded numeric sub-schemas

- Improved handling of non-integer numeric schemas with `multipleOf`
- Improved handling of `not` in many common cases
- Improved handling of object schemas with `dependencies` on required keys
- Fixed cases where `propertyNames` bans a `required` key

- Improved handling of numeric schemas, especially integer schemas with `multipleOf`.
- Bump the minimum version of Hypothesis to ensure that all users have the unique
array bugfix from `0.9.12`.
- Fixed a bug where array schemas with an array of `items`, `additionalItems: false`,
and a `maxItems` larger than the number of allowed items would resolve to an
invalid strategy.

- Improved internal handling of schemas for arrays which must always be length-zero.

- Fixed RFC 3339 strings generation. Thanks to Dmitry Dygalo for the patch!
- Fixed a bug where equal floats and ints could be generated in a unique array,
even though JSONSchema considers 0 === 0.0
(though this may also require an upstream fix to work...)