Plotting vignette failing on master

[gshotwell]

The plotting vignette is failing to build on master which is causing the cube calculations PR to fail. This seems to be coming from a mocking problem. When rendering the vignette I get a GET error looking for api/projects which isn't in the vignette mocks. I've tried the following:

• Delete the vignette data and re-render it to generate fresh mocks
• Ensure that I have the development version of httptest installed
• Ensure that I have the CRAN version of crunch installed (1.214)

[nealrichardson]

Try loadDataset("https://app.crunch.io/api/datasets/307b62/") instead of by its name. My best guess is that the APIs touched in loadDataset changed slightly with the dataset folders work.