Replace COM Tmpls with environmently set COM values

It appears there are many yamls in the GDASApp/parm directory utilize COM tmpl's from the global workflow config.com (e.g., in at least snow and marine parm files). The use of these tmpl's has been frowned upon in the global workflow and we have changed to explicit COM declarations in the j-jobs. I suspect this requirement would extend down into the GDASApp as well. Instead of using these tmpl variables, COM paths should use the COMIN/COMOUT variables defined in the global workflow j-jobs. Some marine parm files (e.g., marine_det_config.yaml) looks already to have implemented this. So, this issue probably should be used to make sure this approach is applied consistently across the GDASApp.