Feature request: choose between distance and time in x-axis of profile

[routeconverter]

In a graph, with the distance in the x-as, data gets distorted because the lower the speed (the lower the increase in distance) the more that data gets shrunk compared to the parts where you moved with a higher speed.

Ok, got it. Implementing time as x-axis has two difficulties

• good usability, precise naming on the surface (currently there is just 'Show profile', I'd like to find better names that horizontal and vertical axis when extending this)
  
• making backing structures more flexible while keeping the optimizations alive that make the profile view work for huge tracks
  

I could need some help there.

ps: thx for the superb track editor !