Implement a solution for separators

[spencerwmiles]

In the current implementation, buttons can be dangerously close together and you may accidentally run a task by accident if moving too quickly.

Add a solution to allow for additional spacing or have an object type that would inject a "|" at minimum if desired.

[FaBjE]

I found playing with the priority argument in createStatusBarItem() that you can re-order the items you add within the scope of the WHOLE status bar. (Not just the items we add)
Given a low/high enough priority it ends up "between" other statusBarItems of other extensions.

I think whatever is done to enhance this it needs to be within the status bar item.
We could add a config option for a kind of "Prefix-Postfix" that is applied for every button.
But on the contrary, is it that much better than just adding it manually?