Refactor documentation for task-based content (#597)

* Refactor docs to task-based content

* Moving stuff around

* Adjusted setup guides and tutorial

* Revising install paths

* Further organization and start of write checks

* Continued work on writing checks and running scans

* Further reorg

* Finalize get started roadmap

* Start of use case guide organization

* More use case guides

* Finish use case guides, reorg and update SodaCL and DS ref

* Continued page revisions to adapt to new structure

* Update connect-dask.md

* Further editing for compliance with task-based.

* Most of CL updates

* Remaining page-by-page updates

* Link adjustments to new structure

* Checking page by page for consistency

* Final page-by-page link check

* Apply redirects

* Link adjustment, added keyword

* Added to docs changelog

* Updated prereqs to include cloud

* Changelog addition; update index

* Removed experimental tags on data sources

Author: janet-can

README.md

@@ -157,15 +157,15 @@ Add a markdown file of your logically-named include content to the `docs/_includ
 
 Relative links:
 ```
-[warehouse yaml]({% link soda-cloud/agreements.md %})
+[warehouse yaml]({% link soda/product-overview.md %})
 
 [airflow_bash.py](/../examples/airflow_bash.py)
 ```
 
 Link to an anchor on a different page:
 
 ```
-[warehouse yaml]({% link soda-cloud/agreements.md %}#to-anchor)
+[warehouse yaml]({% link soda/product-overview.md %}#to-anchor)
 ```
 
 Link to section on same page: