Update History.markdown for the 1.4.0 release
Update the site for the 1.4.0 release

Add a release announcement and update the History file
bump the version number in the code
prep the gemspec for 1.4.0
Use YYYY-MM-DD in History file :)
1.4.0 release post fixes
Merge pull request #1785 from mojombo/release-1.4.0-updates