Replace duplicated `category` feature with `categories`
Add missed tests for categories
Add tests for duplicated categories
fix kramdown urls
Merge pull request #2588 from raboof/patch-2
Update history to reflect merge of #2588 [ci skip]
Updated site history
Mark certain gems as eventually-non-core.
Gracefully require
Put errors/exceptions into Jekyll::Errors module
Merge pull request #2591 from jekyll/extract-list
Update history to reflect merge of #2591 [ci skip]
Merge pull request #2584 from yous/patch-categories-feature
Update history to reflect merge of #2584 [ci skip]
Add Jekyll::AutolinkEmail and Jekyll::GitMetadata

Add these plugins to the list of plugins.
Merge pull request #2596 from ivantsepp/add_ivantsepp_plugins
Update history to reflect merge of #2596 [ci skip]
Fix Textile link

Fix broken link to Textile site to point to RedCloth
Fix loads of other broken links
Add ids to history blocks which are useful.