Installing testthat from GitHub to replace version on Ubuntu repository
https://github.com/hadley/devtools/blob/37bb25855946fa07d6ca855954b317f3e5778257/.travis.yml#L16
reintroducing skip_on_cran(), after using GitHub version of testthat
testthat installed from CRAN, not GitHub, so it mimics CRAN & R-Forge builds better
https://github.com/craigcitro/r-travis/blob/4458f24f46c9754402e9541c35a1eb3355e5e679/scripts/travis-tool.sh#L318
Moving the remaining fixtures back into testthat folder (but now using `skip_on_cran()`)
specifying minimum allowable version of testthat; removing lubridate call in tests
Merge pull request #48 from OuhscBbmc/dev

Adding `skip_on_cran()`