issue #22059; altered stickycheckbox

StickyCheckboxWidget
  - altered 'checked' set/get process to work correctly and to align
    with enyo paradigm
Merge branch 'master' of github.com:xtuple/xtuple into 22059-approve-for-billing
Merge pull request #1210 from tjwebb/22059-approve-for-billing

Issue #22059: fixes to StickyCheckboxWidget