U4-11353 - Have to possibility to start a tour from a content page based on the content type

I created a PR for this : https://github.com/umbraco/Umbraco-CMS/pull/2635

With this PR it is possible to specify a tour is for a specific doctype. On content items a help button will be shown to start the tour for this specific doctype. The tour will not be shown in the help drawer.

This makes it very easy to target a tour for a specific doctype.

I attached a video of the PR in action. I also attached a tour that works for the home page doctype of the starter kit.

I updated the related PR with the following changes :

• It is now possible to have multiple tours for a doctype. Eg. in the started kit there is a composition for navigation & seo. This is reused on multiple doctypes so it's much easier to have one tour for that that is connected to all the doctypes using that composition. I added doctype-v2.json file to demonstrate this. You will need to add the Navigation Base compostion to the home doctype to have it working.
• Tours for a doctype are now moved to the help drawer and are context aware. See the video for a demo.