Shortcodes: use has_shortcode to check if shortcode exists

has_shortcode was introduced in 3.6. It's now safe to use in Jetpack
Contact Form: remove old conditional, oops

Error introduced in  9cc9561fdf596e7e2856f2e0c568c12b1dd1a5e5
Enabling HTTPS for the Tumblr sharing button

The Tumblr image can be served over https, so this change 
uses the http() method to use https when the page uses https.
Changed 4 hard coded links to protocol agnostic

In four places, links were hard coded to http
where the resources were also available over
https. Those links were changed to protocol
agnostic links in order to seamlessly use
the appropriate protocol.
Merge pull request #239 from jeherve/has_shortcode

Shortcodes: use has_shortcode to check for shortcodes in content
Merge pull request #246 from enkrates/sharedaddy-module-ssl

Enabling HTTPS for the Tumblr sharing button