Add tutorials for education subscribers

[4ian]

When unlocked, shown as usual:

When locked:

When clicked despite being locked:

In the classroom tab:

[tristanbob]

You might consider making it more obvious how they get access.
Clicking on a locked icon is not obvious. Perhaps the "Get access" button should always be shown when it is locked?

[4ian]

We might make a new pass on this, for now I'll go ahead with this so we have at least something working/visible :)