LPS-34905 resizable portal script textarea with memory

Hi Julio,

this easy change makes the script textarea resizable using AUI. Dimensions are then stored in portal preferences after each resizing, so next time user visits the Script page (or even just executes the current script), the dimensions are the same as before (for that user).

For this to fully work (no UI restrictions on resizing to the right), this requires https://github.com/juliocamarero/liferay-portal/pull/1729 that I sent you earlier.

Thanks,
Josef