Restructure docs with multiple tutorials

[derickson2402]

Problem

There are tons of learning resources out there for Java and FRC programming, so these docs should not try to reinvent the wheel. Instead, it is most useful to have docs on things that our team specifically needs. I'd like to add several new tutorials that increase in complexity and build off each other.

Solution

There could be multiple sections in the docs which cover increasingly complex topics, and each can build off the others. For example, the beginner stage could be creating a new FRC Java project and making it simply drive, intermediate could start diving into basic autonomous driving and adding an example subsystem, and advanced could add PID controls and dashboards. There could be an additional section of miscellaneous examples that might not fit in like this.

Checklist

The following linked issues are for individual tutorials to be added:

• Move drivetrain tutorial to basics tab #8
• Add intermediate tutorials #9
• Add advanced tutorials #10