multisite licenses changes, move logic to license manager on a per-plugin basis
Merge pull request #1015 from dannyvankooten/feature/network-licenses

multisite licenses changes, move logic to license manager on a per-plugi...
License Manager update.
Bumped version to 1.5.2.7.
Added PHPDocs to test methods, cleaned up class tests, added WPSEO_Rewrite tests.
Merge branch 'master' of github.com:Yoast/wordpress-seo
Increased tested up to version.
Updated el_GR, hu_HU, nl_NL and pl_PL
Updated readme - change log i18n
Update license manager submodule
Added boolean return statements to image_output function.
added WPSEO_Twitter method tests, cleaned up unnecessary ob_clean statements.
add missing text domain to third-party plugin related notices
Merge pull request #1050 from dannyvankooten/bugfix/add-text-domain

add missing text domain to third-party plugin related notices
Merge branch 'master' of git://github.com/Yoast/wordpress-seo into Remove-breadcrumb-enable