new GUI: 2D dynamical system "clicker" and trajectory evolver

[Datseris]

From #250 :

i was working on a more general function, but didn't have the time to finish it: a general 2D clicker, that does what this Poincare GUI does (interactive_poincaresos), but for any "2D" dynamical system. This would work for 2D projected dynamical systems, poincare maps of 3D systems, stroboscopic maps of 2D systems with time forcing, and standard 2D systems (either discrete or continuous).

Would you be interested to do this? In principle it shouldn't be too much work from what you have here. You would make a generic function that directly accepts the actual dynamical system (unlike here where the poincare map is generated inside the function).

[Datseris]

cc @GabrielMajeri