Xamarin.forms: [Enhancement] Blank Forms App in VS and VSMac project template should use Shell

[HobDev]

Summary

New project created using Blank Forms App should default to shell. This will make get starting with shell easier and promote shell to new users.

[knocte]

I disagree, non-Shell templates are still useful.

[HobDev]

Yes they are useful now. But shell is the future and providing blank template for shell will increase its adoption.

[dansiegel]

@HobDev Shell is still far too experimental and needs a lot of baking before they could ever be considered seriously as the new standard.

[HobDev]

@dansiegel Agree, than the solution is to have two blank app templates. Shell Blank App and Classical Blank App.