Acrobot demo throws an error:

I added the main folder to my matlab path. Then went to the folder for the acrobot, openend the main file, ran it and got:

```
Running OptimTraj, iteration 1
  -> Transcription via trapezoid method, nGrid = 20

Unrecognized function or variable 'getIpOptions'.

Error in fmincon (line 860)
    options = getIpOptions(options,sizes.nVar,mEq,flags.constr,defaultopt,10,0.01);
```