[gui] Use a sophisticated docking framework

[Mino260806]

This idea origined from PR #2230
A docking framework would allow users to move code tabs and optional panels freely inside jadx gui, where they would be able to make custom split views in any direction, or move a tab to a seperate window.

@skylot suggested using ModernDocking, but it's still unstable, (at least on linux, see andrewauclair/ModernDocking#218 for example, it's unusable for me).

I'm ready to implement this feature, but I don't know what framework I should use