Allow user to skip the tutorial and/or display it only once

[jpowie01]

Expected Behavior

User should be able to skip the tutorial and/or display tutorial only once.

Actual Behavior

User should walk through the tutorial each time he/she wants to label scans.

Steps to Reproduce the Problem

1. Go to the labeling page.
2. Go through the tutorial.
3. Label scan.
4. Go to the home page.
5. Go to the labeling page.
6. And... you still have to walk through the tutorial. Annoying.