ktsolve: Configurable function for solving families of nonlinear
This function is designed for use with an arbitrary set of equations with
an arbitrary set of unknowns.
The user selects "fixed" values for enough unknowns to leave as many variables as
there are equations, which in most cases means the system is properly
defined and a unique solution exists. The function, the fixed values
and initial values for the remaining unknowns are fed to a nonlinear backsolver.
The original version of "TK!Solver" was the inspiration for this function.