[PIR Action] Improve location documentation for connect modules

Currently, Web Panel, Web Items and Web Section modules' documentation includes only properties descriptions. The `location` property that is supposed to describe where the defined web panel should appear only refers to `Extension Point Finder for Confluence` app which supposed to unveil all possible locations for web panels. The same concept applies to the Page module.

The current documentation structure has following gaps:

• There is no way to get the list of all `locations`
• `Extension Point Finder for Confluence` app displays locations but the app developer still has to navigate through different pages and UI elements to understand which part of the Confluence can be extended
• Some of the locations are rendered on different pages. For example `atl.general`, `atl.footer` are rendered on the home page, page view, page edit, space settings, etc. App developers don't know where exactly these locations are rendered. Confluence developers don't know if any code change affects existing modules. They also don't know what locations should be present in the code they are working on.
• Several locations are rendered differently on different pages. For example we recently introduced a new behavior for `atl.general` on view page where it's rendered as a fixed element as a part of the page header. If user scrolls the confluence page it remains on the page in the header. On other pages it behaves as a normal element and moves up if the user scrolls the page. There is no documentation that describes different behaviors for different pages. 

We should improve the documentation for the `location` property to address all these gaps. 

As a result of this ticket, we should analyze all existing locations, understand better on how web-panels, web-sections and web-items are rendered and create a clear path on how we are going to improve documentation and maintain these modules in a better way.

As an option, we can consider limiting the number of pages where some of web-panels are rendered (like `atl.general` and `atl.footer`) or refactor the position where they are rendered to guarantee that they are shown on all pages and in similar way.