Add text input

[wouterpeere]

Hi @tblanke

I implemented a new option in ScenarioGUI based on the textbox: multiline text box.

Have a look when you have time!

Best,
Wouter

[tblanke]

Hi @wouterpeere ,

It looks fine so far. I have implemented a test and I will merge it in the main branch.

With best regards
@tblanke