Allow Travis to 'parallelize' our tests.
It's a matrix env.
Run the scripts properly.
Don't print out docstrings.
Fix the custom Cucumber output.
Use POSIX::Spawn instead of system to launch Jekyll
Merge pull request #2859 from jekyll/parallelize-tests
Update history to reflect merge of #2859 [ci skip]
prettier exceptions for cucumber. [ci skip]
Fix test for Liquid rendering in Sass.
Add a space because regexp.
Merge pull request #2856 from jekyll/fix-liquid-in-sas
Update history to reflect merge of #2856 [ci skip]
Auto-enable watch on 'serve'.

Addresses @kneath's and @chibicode's comments in #2695.