Add a demo for the extra editors.
Decided on using 'extra:chcekbox' and extra:checkbox_demo as names.
JIN-20 checkboxdemo on android/chrome/ios
Re-focus the field after the value changes.
This is a fix for the unix version of chrome, need to test others.
JIN-21 check box on chrome/safari auto submits.
On safari based browsers, then a change of a checkbox causes
focus to be lost. Work around this.
Documentation and testing updates.