-> Rather than building a script and inserting it in the HTML body every time an editor is created,
   we move the element creation logic in the "initialize" step of the shiny widget.
-> [R] functions (aceEditor, updateAceEditor) create a JSON payload only that is attached to the appropriate element.
-> Shared Javascript code-path for widget initialization, and widget update (shinyAce.js: updateEditor).
-> Make JS <-> server.R communication fully module friendly (selectionId, cursorId, hotkeys).  These are all now reported with a prefix "inputId_"
   (similar to shinyAce_hint).  This is a breaking change.
-> Add couple of examples.