5.1.0

* 5.1.0 / Disable/renable the Shortcodes! module for changes to take
effect.
* 5.1.0 / Verifier shortcode added.  This one is a bit of a beast, so
best to check the documentation.
* 5.1.0 / Verifier: gate content with an age check, or a question.
* 5.1.0 / Verifier: log unique correct and incorrect answers and
optionally show these stats.
* 5.1.0 / Verifier: ability to set a gate as a one time event or not.
Typo