Removed duplicate parameter declaration.

Removed parameter m1_flow_nominal, as this parameter is already
declared in the base class.
Fix for DryCoilDiscretized in OpenModelica.

Reformulated the multiple iterators in the sum function
as this language construct is not supported in OpenModelica.
Added missing each attribute.
Reformulated model.

This avoids warnings from the OpenModelica parser.
Merged Valves from Annex60

This is for OpenModelica compatibility.