Fixes #1270 sequrity question

Fixes error text for sequrity question not wrapping.
fix: Warning time error, refs #1283

* warnings.php
  * expires_period was accessed as numeric value, but is a string
* inc/datahandlers/warnings.php
  * improved handling of expiry for custom warning reasons
* inc/languages/english/datahandler_warnings.lang.php
  * added error message for invalid expires_period
Fixes #1286 SQL error while Upgrade
Fix #1235 Editor post icons

Removed hard coded break after 10 icons.
Added class to label surrounding icons and radiobuttons to keep them
together.
Fix #1235 Editor post icons addition

Missed some things.
Removed variable not needed anymore.
Added correct template version.
Added parameters to render() to expose functionality of underlying get(), updated documentation
Update to use new render function for templates