Return Endomondo support

[penguinolog]

Endomondo support is available in code tree, but not available on website

[Antash]

@penguinolog it is not too easy since endomondo provides access to their api only for partners. I already tried to contact them but they rejected to include tapiirik fork partnership. Another way is to use the nonofficial api (https://github.com/fabulator/endomondo-api) instead but I am not sure I will ever manage to do that. You can lead this if you wish.