Move the building of related posts into their own class
Move the require for related_posts to jekyll.rb
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
Add docs for gist tag.
Update history to reflect addition of docs for gist tag #1072
Add docs for post excerpt #1072
Fix some language problems, props @maul-esel
When talking about post excerpts, be singular about it.
fix upgrade docs
Fixed shading on notes, made it less apparent.
Merge pull request #1101 from sankage/upgrade-docs

relative permalinks in upgrade docs are reversed
Update history to reflect merge of #1101.
Simplified based on cobyism suggestion.
Merge pull request #1089 from zachgersh/cobyism_style

Adds margin to code highlights. Tweaks colorscheme of notes.
Update history to reflect merge of #1089.
Make MaRuKu bend to our will.
The CLI command isn't capitalized :)