Add skill tree and quests to tutorial

[jonjondev]

Feature description

Add skill tree and quests to tutorial, as well as versus other enhancements needed to improve player understanding.

Acceptance criteria/subtasks

• Add quests explanation
• Add skill tree explanation
• Add skip button

TODO

• Add the appropriate label for the feature (i.e. environment, user interface, game logic, etc.)
• Add the feature to the "Development Board"