TODO

[ ] - Conventions:

opts passed to widget constructors.
Widget lifecycle -> constructor -> compile -> update -> destroy.
Naming - Events always on_*.
Renaming - unload -> destroy
Event callback naming -> handler, listener or subscriber?
Strict distinction between DOM event and TS event in docs
Do we want ts as namespace shortcut? Possible confusion with typescript. Alternative?

[ ] - widget.Widget

add_widget
remove_widget
children

[ ] - Button widget in form?

[ ] - Fix collapsible widget.

[ ] - Either include jquery and bootstrap dist here or create dedicated: delivery package with webresource declarations.

[ ] - Change all ajax:* attributes to data-t-ssr-* attributes.

[ ] - Introduce JS instance attaching to DOM nodes and implement an destroy: mechanism in `AjaxHandle.

[ ] - Use document.createTreeWalker in parsers.

[ ] - Move AjaxRequest to request.js -> Request.

[ ] - Move AjaxSpinner to spinner.js -> Spinner.

[ ] - Rename Ajax* to SSR*.

[ ] - AjaxOperation.handle() API consolidation. Instead of opts, all: AjaxOperation deriving objects gets passed elem and event as arguments.
[ ] - Dedicated ajax:event and ajax:action parsing, to allow spaces and: colon in selectors.
[ ] - Add ajax:selector, ajax:mode attributes. and ajax:data: attributes.
[ ] - Support data-t-ajax-* attributes as substitute of ajax:* attributes: and deprecate latter with B/C fallback.
[ ] - Overlay continuation definition should contain overlay instead of: action.