Move the building of related posts into their own class
Fixing paginate_path on windows
Move the require for related_posts to jekyll.rb
Further clarify what paginate_path should do in the case of directories in the path
Wrap tests around Jekyll::RelatedPosts

This gives me more confidence that we're doing the right things when it
comes to both the LSI and non-LSI cases and prevents regressions.
Update the display of the LSI progress output

It now fits more in line with what the other messages display.
Also stub the building of the index

Since we don't actually use the index in getting the related posts from
the tests there's no need to build an index, which can take a long time
if the ruby bindings for the GSL library are not installed.
Added jekyll-contentblocks to the plugins list
new test case: numbers in categories
Add a `data-lang` attribute to code blocks
fix handling of number categories
adjust tests to new test post
Add deprecation support for pages in subfolders with relative permalinks.
Add jekyll doctor command
Better-formatted output with relation to 'Generating... done.'
Add doctor command
Add support for relative permalinks
ensure number category is NOT included as fixnum
Add better language and link to Upgrading page in docs for relative permalinks deprecation msg
Use site config to determine whether permalinks should be relative.