Modified systemtest verify_estimate_r2eff_err_compare_mc() to first use the direct function Jacobian, and then the chi2 derived Jacobian.
This shows the result better.
task #7822(https://gna.org/task/index.php?7822): Implement user function to estimate R2eff and associated errors for exponential curve fitting.
Authored by: tlinnet 2014-08-28
Parent: [r25405]
Child: [r25407]
