*SolverString()
Creates a string within the solver input file.
Syntax
*SolverString(str_name, "str_label")
    Arguments
- str_name
 - The variable name for the solver string.
 - str_label
 - The descriptive label for the solver string.
 
Example
*SolverString( ss_solverstring, "Solver String Label" )
*SetSolverString( ss_solverstring, "String to be used by solver" )
    Context
Comments
The solver string provides a string that can be accessed within the model, for passing into a user subroutine for example.