How can I get the script library path in groovy

Using SoapUI 4.6.2

We have a lot of groovy classes and support files checked into source control. When we pull down a copy of them to test a release it requires updating both the script library location in preferences and then a property that we use to point at the resource file directory.

To get around this I would like to be able to set that path by default to be relative to the script library path. The problem is I have not been able to find anywhere to access that value from inside of a groovy script.

to be clear, I am trying to get access to the script library path set on the pro tab  of the preferences page, not the project level script library setting

So my question is how would I read this value from a groovy step?