Emon.cSoilAbove1m -- incorrect usage of standard name.

[martinjuckes]

Emon.cSoilAbove1m , Carbon Mass in Soil Pool Above 1m Depth, is the carbon content in a soil layer.

It uses the standard name soil_mass_content_of_carbon. The help text of this standard name states: " The "soil content" of a quantity refers to the vertical integral from the surface down to the bottom of the soil model. For the content between specified levels in the soil, standard names including content_of_soil_layer are used.".

At present there is no "content_of_soil_layer" name for carbon content,