Move changelog message to the correct version
Merge branch 'master' of git://github.com/jdevalk/wordpress-seo
Merge branch 'master' of git://github.com/jdevalk/wordpress-seo
Merge branch 'master' of git://github.com/jdevalk/wordpress-seo

Conflicts:
	readme.txt
Bump to 1.4.21
Make sure schedule_yoast_tracking is available for deactivation as well
Re-do of readme line move
Make sure path to functions file is passed properly to the require
Merge branch 'master' of git://github.com/jdevalk/wordpress-seo
Merge pull request #458 from jrfnl/master

Make sure schedule_yoast_tracking is available for deactivation as well and has the correct file path.
Author sitemap logic is broken, props @jrfnl, fixes #464
Prevent saving "empty" values, as suggested in #463