Extension store: new UI

https://xd.adobe.com/view/26c8e935-110d-4ae8-8f00-841ea0759dc2-739b/screen/02f649a5-1183-466d-8237-862cf371d517/

Do UI elements and new page.

Note that the loading must be asynchronous, not like today where the page is blocking for some time.

added to epic &55 (closed)

assigned to @xjouslindenoray and @cfdamedey

mentioned in issue #1190 (closed)

1. Will there be a Search feature?
2. Are Jami Plugins being renamed to Extensions?
3. Will a number be shown indicating many times an extension has been downloaded?
4. Will the latest release date be shown?

Inspiration from Thunderbird and LibreOffice shown below

Add-ons for Thunderbird

LibreOffice Extensions, Documentation and Templates repository

Thank you

mentioned in commit 5530649f

closed