Automatic SISO multiplicative weight determination
Added function to automatically fit a third-order weight to a perturbed plant response. Currently only for SISO and assumes multiplicative uncertainty.
The function runs in perturbed_models as a script on the example system there.
Corrected uncomment of test function and moved routine to function
Corrected one-line docstrings
Created weight_calc function and moved routine there
Merge pull request #69 from SimonStreicher/master

Automatic SISO multiplicative weight determination