Support for users with more then one biceps

[peterrakmanyi]

Is your feature request related to a problem? Please describe.

There is only one input for biceps circumference without differentiation for left or right biceps. Discounting extreme cases, human biceps count range is between 0 - 2 with a median of 2.

Describe the solution you'd like

Duplicate the input for "Biceps circumference" with label prefixes "Left" and "Right".

Describe alternatives you've considered

Amputation, but it is hard to choose. :)