Fix problem where tests crash completely on core branch
Minimize number of tests that fail on core branch.
Merge pull request #66 from r-gaia-cs/improve-glossary-error-message

Improve message for glossary error
Merge pull request #61 from abought/test_rework

Test rework
Add Unit Test target to Makefile
Merge pull request #70 from r-gaia-cs/add-unittest-to-make

Add Unit Test target to Makefile
Fix unittest for changes on motivation.md
Merge pull request #82 from r-gaia-cs/fix-unittests

Fix unittest for changes on motivation.md
Merge pull request #88 from swcarpentry/core

Merge core to avoid warning when check gh-pages