Add documentation for new Strict Mode

[brambrink]

In 10.11, we will introduce a new Strict Mode. This PR adds the documentation for it.

[brambrink]

The introduction of this feature has been postponed to 10.11

[EnasAbdelrazek]

I believe we should mention the improvement made to the save action button rather than just showing the restriction of placing a save button on layouts. Additionally, we have to mention an alternative solution of placing a save button on the layouts like using a snippet.

[brambrink]

Hi, letting you know that this feature is delayed and will be released in 10.12 instead of 10.11

[MariaShaposhnikova]

Hi @brambrink, thanks for the PR! Can we add information on where and how to enable and set up the strict mode? I think we need some guidance on where to find it.

[brambrink]

Thanks Connor and Maria! I've added instructions how to enable strict mode to the docs