Uptil now, users could add tasks to a todo widget only after creating
it through the `/todo` command in the compose box.
Users can now add an initial list of tasks using the `/todo` command,
with each task on a new line in the compose box, where the 1st `:`
would separate a task from its (optional) description. Example:
`/todo\nTask1:description1\nTask2 without description`.
Fixes part of #20213.
Users can now name task lists by providing the task list title in the
`/todo` command on the same line. Example: `/todo School Work`. If no
title is provided by the user, "Task list" (which is also the
placeholder) is used as default.
The author of a task list can later edit / update the task list title
in the todo widget, just like the question in the poll widget.
Fixes part of #20213.
We sent entire 'events' array to 'widgetize.activate' and then
removed its first element(using .shift()); instead we should
send only relevant data ie. the entire array after the first element.
This also helps us avoid an extra check in node tests.
