At the time of creating a page

1. If only 1 layout is selected in the content type, then the system should skip the step to select a layout.
2. If more than 1 layout is selected in the content type, then the Editor will get the option to select a layout from them. 

At the time of Editing a page

The Editor should see only the selected layouts when switching the layouts

Prototype - https://projects.invisionapp.com/d/main?origin=v7#/projects/prototypes/21058682