Suggestion: Update the screenshot

[AllisonXUPR]

In the working with data session, the first screenshot under "Creating a new OpenRefine project" is out of date, it looks different from what I am viewing, I suggest to use a more recent screenshot to replace the current one.

When teaching this part, it is useful for students to see what the preview looks like by clicking through different options, so I suggest to add a note to the session to point out that the preview window will show different data views when the file format changes.

[brownsarahm]

@AllisonXUPR thanks! This is a good fix. Could you submit this as a pull request?

[mariadelmarq]

Latest pull request #78 addresses this issue, cab be safely closed now.

[bencomp]

Confirmed: the screenshot was updated.