cornerstone-v0.1.2

• New: CornerstonePersistentRepositoryMixin to easily add persistence functionality to your repos. Made possible using Hive.
• New: Hive as a dependency for CornerstonePersistentRepositoryMixin.
• New: ConvertExceptionToFailure. A mockable & reusable exception -> failure converter. This way if you have a lot of functions in a repo, doesn't need to keep testing each function for its error handling.
• New: CornerstoneSnapshot. You can use it as base class for your repositories. It have built-in convenience like timestamp.
• New: Example project has been updated to also includes CornerstonePersistentRepositoryMixin usage.