Next release will be v5

[JohnRDOrazio]

Ever since starting to apply static analysis to the project, I realized that I really needed to define classes to represent the JSON data structures, so that the static analyzer could understand the precise shape of arrays and objects, and understand the types associated with every piece of data. Creating all these classes is fundamentally bringing about a lot of refactoring of the codebase. We even refactored all references to festivity, to liturgical_event, to avoid any confusion between festivity as a generic term for a celebration whatever the liturgical grade, and celebrations with a liturgical grade of feast (see issue #239). We are also doing a few other refactors such as in issue #319.

The next release therefore cannot be a minor release, but because of the breaking changes will have to be a major release. Even though not a lot of new functionality is being introduced, we however want to avoid confusion in releasing a minor version with so much refactoring and a few breaking changes. The frontend interface for creating liturgical calendars will also need to be updated to match the new schemas and property names. So basically, until version 5 is released and the frontend interface is updated to match, the https://litcal-staging.johnromanodorazio.com will not be working correctly. Since some of the refactoring on the API development branch has already been pushed to the online server instance, the staging frontend is currently non functional, until it gets an update. However the stable branch frontend at https://litcal.johnromanodorazio.com should still work.