Tutorial Updates

[lukewilliamboswell]

This PR

• Corrects the name of Tags heading to match Table of Contents
• Adds a link to the Task and Error Handling example
• Adds a section to link to the Examples once reader has finished tutorial (before the Advanced section)
• Adds a section on Importing Files at build time
• Adds a section on Record Builder syntax sugar
• Removes the section on Phantom Types

Importing Files Addition

[rtfeldman]

Nice, thank you @lukewilliamboswell! 🎉

I'm gonna take another pass through the tutorial in the next day or so, so this is both helpful and timely! 😃