Separate param.schout output requests

[tomdurrant]

At the moment, schout is one object, reflecting the current structure of the in the param.nml file. However, if outputs are requested for components of the model that are not running, schism fails.

The easiest way around this is to separate outputs requests for each component into separate specifications, and compile them. This is a slight departure from the existing nml structure, but should make things more intutitive