Add some basic tutorials to init.sql

[ansengarvin]

Currently, we have the ability to take tutorial text from the database, but we only have placeholder text.

The next step should be to add some simple, descriptive tutorials to init.sql. It's fine if these are rough drafts, since they're mostly going to be used to demonstrate the prototype. Some ideas of things that might be good to cover:

• Explaining what the similarity search on the protein page is
• Explaining how to use the viewport
• Explaining how the "compare" feature works