Port the simulation to a 2D environment

[jonathanGB]

What logic needs to be modified to work in the new context?

• bubble needs to show a "y" input
• canvas should show the y axis
• signatures taking only "x" should in most/all cases handle y too
• 2D doesn't need a visualization of the origin (at least not as a tick on a line)
• range visualization (orange bar) needs to be a circle
• height of a generation panel is bigger in 2D
• algo to find new position is different (center of smallest circle)
  • split calculator.js into calculator1d.js and calculator2d.js, logic is distinct between the two
• command input needs to add "y" parameters
• save input broken (1d & 2d)

[jonathanGB]

Both 1d and 2d seem stable and work as expected, so I will be merging 2d back into master.

Done!