Override the sort filter
Add scenario
Fallback title based on time
Add scenario for ordering pages without title last
Add generic tests
Add lexicographical sort test
Add more strings tests
Add documentation
Change nils argument to string
Fix markup
Improve the description
Remove the hint aout type
Separate example codes [ci skip]
Follow Ruby Styleguide
Merge pull request #2299 from penibelst/sort-nils