Fixed paths to source code in the documentation
Merge branch 'master' of github.com:webmozart/puli

* 'master' of github.com:webmozart/puli:
  Fixed typo
  Removed line break to avoid messing up Twig's line numbers
  Revert "Set "StrictHostKeyChecking no" in .travis.yml"
  Set "StrictHostKeyChecking no" in .travis.yml
  Updated Composer dependencies
  Adapted .travis.yml to hopefully fix the Travis CI build
  Made PuliCssRewriteFilter hashable and fixed exception message