Output a feasible point

[mkovari]

VMCON and PyVMCON frequently fail to converge.

Proposed solution

VMCON has an algorithm to find a feasible point to the linearized constraints (a solution vector that satisfies the constraints) as a starting point for each iteration. (PyVMCON does not seem to have this.) It would be a spiffing idea to store the first feasible point found (if there is one) and output it if the optimiser fails.

Drawbacks

We would need to find the relevant bit of code in VMCON. Also, VMCON is not allowed in the GitHub repository.

@jonmaddock @timothy-nunn