Update CHANGELOG with latest additions and changes

This commit introduces numerous changes outlined in the CHANGELOG. Major updates include sending full websocket url in player_info and achieving ">90"% code coverage in tests. Several modifications were also made such as refactoring extra_setup_functions, allowing study config overwriting environment config attributes, and changing time comparisons convention. Player config in the environment class has also been refactored to a dataclass.

CHANGELOG.md

@@ -13,8 +13,22 @@
 
 ### Added
 
+- Send full websocket url in player_info.
+- ">90"% code coverage in tests
+
 ### Changed
 
+- `extra_setup_functions` now only contain hook callback classes (`hook_callbacks`). Therefore, the `func` and `kwargs`
+  fields were
+  removed and the kwargs are now the standard values for defined hooks. This reduced the complexity of the config.
+- The study config can now overwrite environment config attributes. This reduces the need to copy environment configs
+  for each level in the config.
+- Most time comparisons (countdowns, etc.) are now compared with `<=` and not `<`. This is handy for testing and
+  definition.
+- Player config in the environment class is now a dataclass and not a dict. The content remains the same. Just the
+  access changes from dict access to normal object like access.
+- Some type hint additions
+
 ### Deprecated
 
 ### Removed