v1.0.0 - First stable release!

This is the first stable release!
That means that all the basic features are implemented, the next minor releases will just be bug fixes or small improvements :D

What changed?

• removed validation of API responses as there will (hopefully) be no breaking changes made by WebUntis - if there are any, it'll crash either way
• added wrapper classes with helper methods to all elements that have datetimes

The next big feature will be an improvement of the Period class and will add methods to compare lessons, find duplicates etc.