Add forced "show empty sections" option per project

We have 2 project types:

• many sections, many can be empty, is not something you would like to see all, since it takes a lot of space, and is enough to go there when needed with button or from subtask in details panel
• small projects, mostly for less technical people, where is maximum a few sections, and they should be always visible, so they can add tasks in correct places easily (ofc it could be achieved with using colored task instead actual section, but section has more visual tweaks + block of completion)

So such option would cover second case.