Add Jekyll v1.2.0 release post.
Update History.markdown.
Update Jekyll::VERSION
Update gemspec for release of v1.2.
Remove Kramdown dep from README. #1498
Change 'version `--drafts`' to 'version of `--drafts`'
Move Kramdown to the development dependency section
Merge pull request #1510 from mojombo/release-1.2

Release v1.2