strip shortcodes should be during input post, not output
change shortcodes api to OO
Separating default shortcode from shortcodes library. Now support extensions-shortcodes
rename shortcodes_api to shortcode and shortcode directly extend controller
link_brand compatibility 1.5.3.1 n older. Add image shortcode
version change to rc.3
Update README.md
Merge remote-tracking branch 'upstream/master'