Retrieving gems from rubygems via HTTPS
Update dependencies: kramdown, rake, shoulda, cucumber, redcarpet

Kramdown: 0.13.4 => 0.14.1
Rake: 0.9 => 10.0.3
Shoulda: 2.11 => 3.3.2
Redcarpet: 2.1.1 => 2.2.2
Require test/unit in test helper.rb for execution of unit tests
Fix Kramdown tests: they now use numerical HTML entities
Update History.txt for 0.12.1 release.
Bump version in gemspec and in jekyll.rb
Relax Kramdown requirement to 0.14 instead of 0.14.1
Update date in gemspec
Release 0.12.1
Avoid breaking change in latest directory_watcher

We need to be a little more pressimistic about the directory_watcher
gem, since it's latest version (1.5) breaks jekyll's --auto option.

Fixes mojombo/jekyll#882.
Merge pull request #883 from liliakai/0.12.1-release

Avoid breaking change in latest directory_watcher
Json generator by Jekyll for Android