UI: replace dynamic/static with single icon

[ivokwee]

The labels 'dynamic' 'static' take too much space in the header. We can replace by a checkbox-style button with an appropriate icon. Some idea is a finger like one of theese below.

[ESCRI11]

I think the space issue only becomes relevant if you use the platform with a really small screen (or zoomed-in), at which point the whole platform is messy not just the headers.

Also, the plotmodule implementation is designed to have multiple possible tabs, not just 2 (static/dynamic), therefore a checkbox would require a re-implementation of the multi-tab feature. If you find it relevant I will do it, I don't think the effort is worth it.

A middle ground approach could be using 2 icons, I think it will be slightly confusing for users but we can try.