Ensure the 'tmp' dir exists before running tests
Merge pull request #236 from opscode/ensure-tmp-dir-exists

Ensure the 'tmp' dir exists before running tests
Cookbook versions have their own show page.

Its template is more or less copied directly from cookbooks/show. If we
determine that the two should remain in near-lockstep, we can extract
partials for the job.
Order cookbook versions on a monotonic attribute
Cookbooks link to each of their published versions
JS specs are passing, and running on Travis