Add video specifications in our documentation

[khushal87]

Motivation Improve the documentation by adding the video feature-related stuff in it.

Proposed solution I would like you to add a video section to our docs (just like push notifications) where we summarise the following:

• [ ] in which version the feature introduced
• [ ] enabling CDN v2 (different pricing and link to what it will cost)
• [ ] enabling it via optional install- steps

Acceptance Criteria

Add the above points to our documentation by creating a section for it.