Teach Travis to fail on trailing whitespace.
Merge pull request #813 from Gaelan/travis_whitespace

Teach Travis to fail on trailing whitespace.
Fix the Travis build.
Surround the trailing whitespace check in quotes.
Fix travis.yml syntax.
Merge pull request #814 from Gaelan/travis_whitespace_hotfix

Fix the Travis build.
Update link to CLI
Refactor stash api tests
markdown: don't double-escape ">" and "<" in code blocks
Merge pull request #816 from mjhoy/416-dont-double-escape-lt-gt

markdown: don't double-escape ">" and "<" in code blocks
sanitize markdown output

Previously, a carefully crafted code submission could introduce
unsafe HTML into a submissions page.
Fix exercise submission text on profile page.

When visiting another user's profile page, it reports that we have not
submitted an exercise lately.
Merge pull request #822 from gavinlaking/issues/820

Fix exercise submission text on profile page.