Allow switching between distance and time in elevation profile

[mu88]

Hi,

I just noticed that due to using clock time in the elevation profile, it gets distorted when having a longer break. For example, see the following elevation profile from one of my workouts:

As you can see, there is a plateau between 12:20 and 12:30 - but I did not ride on a plateau, instead I took a break 🙂

I see at least three options:

1. Use the duration without pauses instead of clock time.
2. Use kilometers instead of clock time.
3. Having a switch to toggle between clock time, duration without pauses, and kilometers.

As always, thx for your great work 👏🏻

[bastianjoel]

Distance graph was added in #647.

#647 (comment)

I think it would be nice to have both duartion where pauses are removed and time of day graphs.